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Michael J. Therien

William R. Kenan, Jr. Distinguished Professor of Chemistry
Chemistry
Box 90346, Durham, NC 27708-0346
5330 French Family Science Cen, Durham, NC 27708

Selected Publications


Coherence in Chemistry: Foundations and Frontiers.

Journal Article Chemical reviews · November 2024 Coherence refers to correlations in waves. Because matter has a wave-particle nature, it is unsurprising that coherence has deep connections with the most contemporary issues in chemistry research (e.g., energy harvesting, femtosecond spectroscopy, molecul ... Full text Cite

Fluence-Dependent Photoinduced Charge Transfer Dynamics in Polymer-Wrapped Semiconducting Single-Walled Carbon Nanotubes.

Journal Article Journal of the American Chemical Society · November 2024 Because an individual single-walled carbon nanotube (SWNT) can absorb multiple photons, the exciton density within a single tube depends upon excitation conditions. In SWNT-based energy conversion systems, interactions between excitons and charges make it ... Full text Cite

Efficiency Limits of Energy Conversion by Light-Driven Redox Chains.

Journal Article Journal of the American Chemical Society · November 2024 The conversion of absorbed sunlight to spatially separated electron-hole pairs is a crucial outcome of natural photosynthesis. Many organisms achieve near-unit quantum yields of charge separation (one electron-hole pair per incident photon) by dissipating ... Full text Cite

Band gap opening of metallic single-walled carbon nanotubes via noncovalent symmetry breaking.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · March 2024 Covalent bonding interactions determine the energy-momentum (E-k) dispersion (band structure) of solid-state materials. Here, we show that noncovalent interactions can modulate the E-k dispersion near the Fermi level of a low-di ... Full text Cite

Electron Spin Polarization and Rectification Driven by Chiral Perylene Diimide-Based Nanodonuts.

Journal Article The journal of physical chemistry letters · November 2023 The chirality-induced spin selectivity (CISS) effect allows thin-film layers of chiral conjugated molecules to function as spin filters at ambient temperature. Through solvent-modulated dropcasting of chiral l- and d-perylene diimide (PDI) monomeric buildi ... Full text Cite

Synthesis and functionalization of electron-deficient perfluoroalkyl porphyrin building blocks for supermolecular systems

Journal Article Journal of Porphyrins and Phthalocyanines · May 1, 2023 Synthetic strategies for electron-deficient meso-perfluoroalkylporphyrins bearing diverse functional groups are described. Scalable and efficient syntheses for 5-triisopropylsilylethynyl-10,15,20-tris(heptafluoropropyl)porphyrin and 5-triisopropylsilylethy ... Full text Cite

All-Carbon Thin-Film Transistors Using Water-Only Printing.

Journal Article Nano letters · March 2023 Printing thin-film transistors (TFTs) using nanomaterials is a promising approach for future electronics. Yet, most inks rely on environmentally harmful solvents for solubilizing and postprint processing the nanomaterials. In this work, we demonstrate wate ... Full text Cite

Ionic dielectrics for fully printed carbon nanotube transistors: impact of composition and induced stresses.

Journal Article Nanoscale · November 2022 Printed carbon nanotube thin-film transistors (CNT-TFTs) are candidates for flexible electronics with printability on a wide range of substrates. Among the layers comprising a CNT-TFT, the gate dielectric has proven most difficult to additively print owing ... Full text Cite

Regulating Singlet-Triplet Energy Gaps through Substituent-Driven Modulation of the Exchange and Coulomb Interactions.

Journal Article Journal of the American Chemical Society · August 2022 Control of the singlet-triplet energy gap (ΔEST) is central to realizing productive energy conversion reactions, photochemical reaction trajectories, and emergent applications that exploit molecular spin physics. Despite this, no systemat ... Full text Cite

Synthetic Control of Exciton Dynamics in Bioinspired Cofacial Porphyrin Dimers.

Journal Article Journal of the American Chemical Society · April 2022 Understanding how the complex interplay among excitonic interactions, vibronic couplings, and reorganization energy determines coherence-enabled transport mechanisms is a grand challenge with both foundational implications and potential payoffs for energy ... Full text Cite

Twisted molecular wires polarize spin currents at room temperature.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · February 2022 A critical spintronics challenge is to develop molecular wires that render efficiently spin-polarized currents. Interplanar torsional twisting, driven by chiral binucleating ligands in highly conjugated molecular wires, gives rise to large near-infrared ro ... Full text Cite

Excited-State Dynamics and Nonlinear Optical Properties of Hyperpolarizable Chromophores Based on Conjugated Bis(terpyridyl)Ru(II) and Palladium and Platinum Porphyrinic Components: Impact of Heavy Metals upon Supermolecular Electro-Optic Properties.

Journal Article Inorganic chemistry · October 2021 A new series of strongly coupled oscillators based upon (porphinato)Pd, (porphinato)Pt, and bis(terpyridyl)ruthenium(II) building blocks is described. These RuPPd, RuPPt, RuPPdRu, and RuPPtRu chromophores feature bis(terpyridyl) ... Full text Cite

Spinning Molecules, Spinning Spins: Modulation of an Electron Spin Exchange Interaction in a Highly Anisotropic Hyperfine Field.

Journal Article ACS omega · October 2021 An investigation of spin and conformational dynamics in a series of symmetric Cu-Cu porphyrin dimer solutions is presented using electron paramagnetic resonance (EPR) spectroscopy. Previous spectral simulations focused on the isotropic exchange interaction ... Full text Cite

EPR of Photoexcited Triplet-State Acceptor Porphyrins.

Journal Article The journal of physical chemistry. C, Nanomaterials and interfaces · June 2021 The photoexcited triplet states of porphyrin architectures are of significant interest in a wide range of fields including molecular wires, nonlinear optics, and molecular spintronics. Electron paramagnetic resonance (EPR) is a key spectroscopic tool in th ... Full text Cite

Printable and recyclable carbon electronics using crystalline nanocellulose dielectrics.

Journal Article Nature electronics · April 2021 Electronic waste can lead to the accumulation of environmentally and biologically toxic materials and is a growing global concern. Developments in transient electronics-in which devices are designed to disintegrate after use-have focused on increasing the ... Full text Cite

De Novo Design, Solution Characterization, and Crystallographic Structure of an Abiological Mn-Porphyrin-Binding Protein Capable of Stabilizing a Mn(V) Species.

Journal Article Journal of the American Chemical Society · January 2021 De novo protein design offers the opportunity to test our understanding of how metalloproteins perform difficult transformations. Attaining high-resolution structural information is critical to understanding how such designs function. There have bee ... Full text Cite

Allosteric cooperation in a de novo-designed two-domain protein.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · December 2020 We describe the de novo design of an allosterically regulated protein, which comprises two tightly coupled domains. One domain is based on the DF (Due Ferri in Italian or two-iron in English) family of de novo proteins, which have a diiron cofactor that ca ... Full text Cite

Topology, Distance, and Orbital Symmetry Effects on Electronic Spin-Spin Couplings in Rigid Molecular Systems: Implications for Long-Distance Spin-Spin Interactions.

Journal Article The journal of physical chemistry. A · September 2020 Featured Publication Understanding factors that underpin the signs and magnitudes of electron spin-spin couplings in biradicaloids, especially those that are integrated into highly delocalized electronic structures, promises to inform the design of molecular spintronic systems ... Full text Cite

Electronic structure and photophysics of a supermolecular iron complex having a long MLCT-state lifetime and panchromatic absorption.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · August 2020 Featured Publication Exploiting earth-abundant iron-based metal complexes as high-performance photosensitizers demands long-lived electronically excited metal-to-ligand charge-transfer (MLCT) states, but these species suffer typically from femtosecond timescale charge-transfer ... Full text Cite

Driving high quantum yield NIR emission through proquinoidal linkage motifs in conjugated supermolecular arrays.

Journal Article Chemical science · August 2020 Featured Publication High quantum yield NIR fluorophores are rare. Factors that drive low emission quantum yields at long wavelength include the facts that radiative rate constants increase proportional to the cube of the emission energy, while nonradiative rate constants incr ... Full text Cite

Tribute to David N. Beratan.

Journal Article The journal of physical chemistry. B · April 2020 Full text Cite

Distance Dependence of Electronic Coupling in Rigid, Cofacially Compressed, π-Stacked Organic Mixed-Valence Systems.

Journal Article The journal of physical chemistry. B · February 2020 A series of new π-stacked compounds, 1,8-bis(2',5'-dimethoxybenzene-1'-yl)naphthalene (1), 1,4-bis(8'-(2″,5″-dimethoxybenzene-1″-yl)naphthalen-1'-yl)benzene (2), and 1,8-bis(4'-(8″-(2‴,5‴-dimethoxybenzene-1‴-yl)naphthalen-1″-yl)benzene-1'-yl) ... Full text Cite

Fully printed, all-carbon, recyclable electronics

Journal Article · 2020 The rapid growth of electronic waste must be curtailed to prevent accumulation of environmentally and biologically toxic materials, which are essential to traditional electronics1. The recent proliferation of transient electronics has focused predominantly ... Full text Cite

De Novo Design, Solution Characterization, and Crystallographic Structure of an Abiological Mn-Porphyrin Binding Protein Capable of Stabilizing a Mn(V) Species

Journal Article · 2020 De novo protein design offers the opportunity to test our understanding of how metalloproteins perform difficult transformations. Attaining high-resolution structural information is critical to understanding how such designs function. There have been many ... Full text Cite

Low-Resistance Molecular Wires Propagate Spin-Polarized Currents.

Journal Article Journal of the American Chemical Society · September 2019 Spin based properties, applications, and devices are typically related to inorganic ferromagnetic materials. The development of organic materials for spintronic applications has long been encumbered by its reliance on ferromagnetic electrodes for polarized ... Full text Cite

Excitation energy-dependent photocurrent switching in a single-molecule photodiode.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · August 2019 The direction of electron flow in molecular optoelectronic devices is dictated by charge transfer between a molecular excited state and an underlying conductor or semiconductor. For those devices, controlling the direction and reversibility of electron flo ... Full text Cite

Mapping hole hopping escape routes in proteins.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · August 2019 A recently proposed oxidative damage protection mechanism in proteins relies on hole hopping escape routes formed by redox-active amino acids. We present a computational tool to identify the dominant charge hopping pathways through these residues based on ... Full text Cite

Engineering opposite electronic polarization of singlet and triplet states increases the yield of high-energy photoproducts.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · July 2019 Efficient photosynthetic energy conversion requires quantitative, light-driven formation of high-energy, charge-separated states. However, energies of high-lying excited states are rarely extracted, in part because the congested density of states in the ex ... Full text Cite

Quantitative Evaluation of Optical Free Carrier Generation in Semiconducting Single-Walled Carbon Nanotubes.

Journal Article Journal of the American Chemical Society · November 2018 Gauging free carrier generation (FCG) in optically excited, charge-neutral single-walled carbon nanotubes (SWNTs) has important implications for SWNT-based optoelectronics that rely upon conversion of photons to electrical current. Earlier investigations h ... Full text Open Access Cite

Carrier Dynamics Engineering for High-Performance Electron-Transport-Layer-free Perovskite Photovoltaics

Journal Article Chem · October 11, 2018 Electron-transport-layer-free (ETL-free) device architectures are promising designs for perovskite photovoltaics because they offer simpler configurations, low cost, and convenience for versatile optoelectronics. However, the development of ETL-free photov ... Full text Open Access Cite

Solvent- and Wavelength-Dependent Photoluminescence Relaxation Dynamics of Carbon Nanotube sp3 Defect States.

Journal Article ACS nano · August 2018 Photoluminescent sp3 defect states introduced to single wall carbon nanotubes (SWCNTs) through low-level covalent functionalization create new photophysical behaviors and functionality as a result of defect sites acting as exciton traps. Evaluation of rela ... Full text Cite

Unusual solvent polarity dependent excitation relaxation dynamics of a bis[: P -ethynyldithiobenzoato]Pd-linked bis[(porphinato)zinc] complex

Journal Article Molecular Systems Design and Engineering · February 1, 2018 We report the synthesis and excited-state dynamics of a bis[p-ethynyldithiobenzoato]Pd(ii)-bridged bis[(porphinato) zinc(ii)] complex (PZn-Pd(edtb)2-PZn) that exhibits unusual solvent dielectric (ϵ)-dependent excited-state relaxation behavior. In nonpolar ... Full text Cite

Dynamics of charged excitons in electronically and morphologically homogeneous single-walled carbon nanotubes.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · January 2018 The trion, a three-body charge-exciton bound state, offers unique opportunities to simultaneously manipulate charge, spin, and excitation in one-dimensional single-walled carbon nanotubes (SWNTs) at room temperature. Effective exploitation of trion quasi-p ... Full text Cite

Real-time dose-rate monitoring with gynecologic brachytherapy: Results of an initial clinical trial.

Journal Article Brachytherapy · 2018 PURPOSE: A nanoscintillator-based fiber-optic dosimeter (nanoFOD) was developed to measure real-time dose rate during high-dose-rate (HDR) brachytherapy. A trial was designed to prospectively test clinical feasibility in gynecologic implants. METHODS AND M ... Full text Link to item Cite

De novo design of a hyperstable non-natural protein-ligand complex with sub-Å accuracy.

Journal Article Nature chemistry · December 2017 Protein catalysis requires the atomic-level orchestration of side chains, substrates and cofactors, and yet the ability to design a small-molecule-binding protein entirely from first principles with a precisely predetermined structure has not been demonstr ... Full text Cite

Molecular Road Map to Tuning Ground State Absorption and Excited State Dynamics of Long-Wavelength Absorbers.

Journal Article Journal of the American Chemical Society · November 2017 Realizing chromophores that simultaneously possess substantial near-infrared (NIR) absorptivity and long-lived, high-yield triplet excited states is vital for many optoelectronic applications, such as optical power limiting and triplet-triplet annihilation ... Full text Cite

Additive engineering for high-performance room-temperature-processed perovskite absorbers with micron-size grains and microsecond-range carrier lifetimes

Journal Article Energy and Environmental Science · November 1, 2017 Perovskite photovoltaics have attracted remarkable attention recently due to their exceptional power conversion efficiencies (PCE). State-of-the-art perovskite absorbers typically require thermal annealing steps for high film quality. However, the annealin ... Full text Cite

NIR-emissive PEG-b-TCL micelles for breast tumor imaging and minimally invasive pharmacokinetic analysis.

Journal Article Nanoscale · September 21, 2017 Motivated by the goal of developing a fully biodegradable optical contrast agent with translational clinical potential, a nanoparticle delivery vehicle was generated from the self-assembly of poly(ethylene-glycol)-block-poly(trimethylene carbonate-co-capro ... Full text Link to item Cite

Controlling the excited-state dynamics of low band gap, near-infrared absorbers via proquinoidal unit electronic structural modulation.

Journal Article Chemical science · September 2017 While the influence of proquinoidal character upon the linear absorption spectrum of low optical bandgap π-conjugated polymers and molecules is well understood, its impact upon excited-state relaxation pathways and dynamics remains obscure. We report the s ... Full text Cite

Alkyne-Bridged Multi[Copper(II) Porphyrin] Structures: Nuances of Orbital Symmetry in Long-Range, Through-Bond Mediated, Isotropic Spin Exchange Interactions.

Journal Article Journal of the American Chemical Society · July 2017 Spin and conformational dynamics in symmetric alkyne-bridged multi[copper(II) porphyrin] structures have been studied in toluene solution at variable temperature using steady-state electron paramagnetic resonance (EPR) spectroscopy. Comparison of the dimer ... Full text Cite

Engineering High-Potential Photo-oxidants with Panchromatic Absorption.

Journal Article Journal of the American Chemical Society · June 2017 Challenging photochemistry demands high-potential visible-light-absorbing photo-oxidants. We report (i) a highly electron-deficient Ru(II) complex (eDef-Rutpy) bearing an E1/20/+ potential more than 300 mV more positive than that of a ... Full text Cite

On the Importance of Electronic Symmetry for Triplet State Delocalization.

Journal Article Journal of the American Chemical Society · April 2017 The influence of electronic symmetry on triplet state delocalization in linear zinc porphyrin oligomers is explored by electron paramagnetic resonance techniques. Using a combination of transient continuous wave and pulse electron nuclear double resonance ... Full text Cite

Synthesis and characterization of Na(Gd0.5Lu0.5)F4: Nd3+,a core-shell free multifunctional contrast agent.

Journal Article Journal of alloys and compounds · February 2017 Compared to conventional core-shell structures, core-shell free nanoparticles with multiple functionalities offer several advantages such as minimal synthetic complexity and low production cost. In this paper, we present the synthesis and characterization ... Full text Cite

Large Hyperpolarizabilities at Telecommunication-Relevant Wavelengths in Donor-Acceptor-Donor Nonlinear Optical Chromophores.

Journal Article ACS central science · December 2016 Octopolar D2-symmetric chromophores, based on the MPZnM supermolecular motif in which (porphinato)zinc(II) (PZn) and ruthenium(II) polypyridyl (M) structural units are connected via ethyne linkages, were synthesized. These structures take ... Full text Open Access Cite

Mean First-Passage Times in Biology.

Journal Article Israel journal of chemistry · November 2016 Many biochemical processes, such as charge hopping or protein folding, can be described by an average timescale to reach a final state, starting from an initial state. Here, we provide a pedagogical treatment of the mean first-passage time (MFPT) of a phys ... Full text Cite

First-order hyperpolarizabilities of chiral, polymer-wrapped single-walled carbon nanotubes.

Journal Article Chemical communications (Cambridge, England) · October 2016 We report the first-order hyperpolarizabilities (βHRS values) of individualized, length-sorted (700 ± 50 nm long) (6,5) SWNTs and corresponding polymer-wrapped (6,5) SWNT superstructures. These SWNT-based nanohybrids feature semiconducting polym ... Full text Cite

Real Time Dosimetry for Gynecologic Brachytherapy: Initial Results of a Prospective Clinical Trial (vol 93, pg S203, 2015)

Journal Article INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS · June 1, 2016 Link to item Cite

WE-DE-201-07: Measurement of Real-Time Dose for Tandem and Ovoid Brachytherapy Procedures Using a High Precision Optical Fiber Radiation Detector.

Journal Article Med Phys · June 2016 PURPOSE: Development of a novel on-line dosimetry tool is needed to move toward patient-specific quality assurance measurements for Ir-192 HDR brachytherapy to verify accurate dose delivery to the intended location. This work describes the development and ... Full text Link to item Cite

Photoinduced Electron Transfer Elicits a Change in the Static Dielectric Constant of a de Novo Designed Protein.

Journal Article Journal of the American Chemical Society · February 2016 We provide a direct measure of the change in effective dielectric constant (ε(S)) within a protein matrix after a photoinduced electron transfer (ET) reaction. A linked donor-bridge-acceptor molecule, PZn-Ph-NDI, consisting of a (porphinato)Zn donor (PZn), ... Full text Cite

Valence Band Dependent Charge Transport in Bulk Molecular Electronic Devices Incorporating Highly Conjugated Multi-[(Porphinato)Metal] Oligomers.

Journal Article Journal of the American Chemical Society · February 2016 Molecular electronics offers the potential to control device functions through the fundamental electronic properties of individual molecules, but realization of such possibilities is typically frustrated when such specialized molecules are integrated into ... Full text Cite

Extreme electron polaron spatial delocalization in π-conjugated materials.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · November 2015 The electron polaron, a spin-1/2 excitation, is the fundamental negative charge carrier in π-conjugated organic materials. Large polaron spatial dimensions result from weak electron-lattice coupling and thus identify materials with unusually low barriers f ... Full text Cite

Defusing redox bombs?

Journal Article Proceedings of the National Academy of Sciences of the United States of America · September 2015 Full text Cite

Unambiguous Diagnosis of Photoinduced Charge Carrier Signatures in a Stoichiometrically Controlled Semiconducting Polymer-Wrapped Carbon Nanotube Assembly.

Journal Article Angewandte Chemie (International ed. in English) · July 2015 Single-walled carbon nanotube (SWNT)-based nanohybrid compositions based on (6,5) chirality-enriched SWNTs ([(6,5) SWNTs]) and a chiral n-type polymer (S-PBN(b)-Ph4 PDI) that exploits a perylenediimide (PDI)-containing repeat unit are reported; S-PBN(b)-Ph ... Full text Cite

Electron Spin Relaxation of Hole and Electron Polarons in π-Conjugated Porphyrin Arrays: Spintronic Implications.

Journal Article The journal of physical chemistry. B · June 2015 Electron spin resonance (ESR) spectroscopic line shape analysis and continuous-wave (CW) progressive microwave power saturation experiments are used to probe the relaxation behavior and the relaxation times of charged excitations (hole and electron polaron ... Full text Cite

Near-Infrared-to-Visible Photon Upconversion Enabled by Conjugated Porphyrinic Sensitizers under Low-Power Noncoherent Illumination.

Conference The journal of physical chemistry. A · June 2015 We report four supermolecular chromophores based on (porphinato)zinc(II) (PZn) and (polypyridyl)metal units bridged via ethyne connectivity (Pyr1RuPZn2, Pyr1RuPZnRuPyr1, Pyr1RuPZn2RuPyr1, and OsPZn2Os) that fulfill critical sensitizer requirements for NIR- ... Full text Cite

Single-Step Assembly of Multimodal Imaging Nanocarriers: MRI and Long-Wavelength Fluorescence Imaging.

Journal Article Advanced healthcare materials · June 2015 Magnetic resonance imaging (MRI)- and near-infrared (NIR)-active, multimodal composite nanocarriers (CNCs) are prepared using a simple one-step process, flash nanoprecipitation (FNP). The FNP process allows for the independent control of the hydrodynamic d ... Full text Cite

Fiber-optic detector for real time dosimetry of a micro-planar x-ray beam.

Journal Article Medical physics · April 2015 PurposeHere, the authors describe a dosimetry measurement technique for microbeam radiation therapy using a nanoparticle-terminated fiber-optic dosimeter (nano-FOD).MethodsThe nano-FOD was placed in the center of a 2 cm diameter mouse pha ... Full text Cite

Caging metal ions with visible light-responsive nanopolymersomes.

Journal Article Langmuir : the ACS journal of surfaces and colloids · January 2015 Polymersomes are bilayer vesicles that self-assemble from amphiphilic diblock copolymers, and provide an attractive system for the delivery of biological and nonbiological molecules due to their environmental compatibility, mechanical stability, synthetic ... Full text Cite

Design of diethynyl porphyrin derivatives with high near infrared fluorescence quantum yields

Journal Article Journal of Porphyrins and Phthalocyanines · January 1, 2015 A design strategy for (porphinato)zinc-based fluorophores that possess large near infrared fluorescence quantum yields is described. These fluorophores are based on a (5,15-diethynylporphinato)zinc(II) framework and feature symmetric donor or acceptor unit ... Full text Cite

Electronic and optical properties of Er-doped Y2O2S phosphors

Journal Article Journal of Materials Chemistry C · January 1, 2015 In this paper, we report a detailed computational and experimental investigation of the structural, electronic and dynamic properties of undoped and Er3+-doped Y2O2S phosphors by using computational crystal field (CF) calculations and electronic density of ... Full text Cite

Tailoring porphyrin-based electron accepting materials for organic photovoltaics.

Conference Journal of the American Chemical Society · December 2014 The syntheses, potentiometric responses, optical spectra, electronic structural properties, and integration into photovoltaic devices are described for ethyne-bridged isoindigo-(porphinato)zinc(II)-isoindigo chromophores built upon either electron-rich 10, ... Full text Cite

Femtosecond pulse train shaping for accurate two-photon excited fluorescence measurements

Conference Optics InfoBase Conference Papers · October 14, 2014 We report a simple measurement method that exploits pulse train shaping to suppress linear contributions to the fluorescence, and allows for extraction of the two-photon absorption cross sections. © 2014 OSA. ... Full text Cite

Potentiometric, electronic, and transient absorptive spectroscopic properties of oxidized single-walled carbon nanotubes helically wrapped by ionic, semiconducting polymers in aqueous and organic media.

Journal Article Journal of the American Chemical Society · October 2014 We report the first direct cyclic voltammetric determination of the valence and conduction band energy levels for noncovalently modified (6,5) chirality enriched SWNTs [(6,5) SWNTs] in which an aryleneethynylene polymer monolayer helically wraps the nanotu ... Full text Cite

Hapticity-dependent charge transport through carbodithioate-terminated [5,15-bis(phenylethynyl)porphinato]zinc(II) complexes in metal-molecule-metal junctions.

Journal Article Nano letters · October 2014 Single molecule break junction experiments and nonequilibrium Green's function calculations using density functional theory (NEGF-DFT) of carbodithioate- and thiol-terminated [5,15-bis(phenylethynyl)-10,20-diarylporphinato]zinc(II) complexes reveal the imp ... Full text Cite

Europium- and lithium-doped yttrium oxide nanocrystals that provide a linear emissive response with X-ray radiation exposure.

Journal Article Nanoscale · May 21, 2014 Eu- and Li-doped yttrium oxide nanocrystals [Y2-xO3; Eux, Liy], in which Eu and Li dopant ion concentrations were systematically varied, were developed and characterized (TEM, XRD, Raman spectroscopic, UV-excited lifetime, and ICP-AES data) in order to def ... Full text Link to item Cite

Biochemistry and theory of proton-coupled electron transfer.

Journal Article Chemical reviews · April 2014 Full text Cite

Fluence-dependent singlet exciton dynamics in length-sorted chirality-enriched single-walled carbon nanotubes.

Journal Article Nano letters · February 2014 We utilize individualized, length-sorted (6,5)-chirality enriched single-walled carbon nanotubes (SWNTs) having dimensions of 200 and 800 nm, femtosecond transient absorption spectroscopy, and variable excitation fluences that modulate the exciton density ... Full text Cite

One-Pot Solvothermal Synthesis of Highly Emissive, Sodium-Codoped, LaF₃ and BaLaF₅ Core-Shell Upconverting Nanocrystals.

Journal Article Nanomaterials (Basel, Switzerland) · January 2014 We report a one-pot solvothermal synthesis of sub-10 nm, dominant ultraviolet (UV) emissive upconverting nanocrystals (UCNCs), based on sodium-codoped LaF₃ and BaLaF₅ (0.5%Tm; 20%Yb) and their corresponding core@shell derivatives. Elemental analysis shows ... Full text Cite

Femtosecond pulse train shaping for accurate two-photon excited fluorescence measurements

Conference Laser Science, LS 2014 · January 1, 2014 We report a simple measurement method that exploits pulse train shaping to suppress linear contributions to the fluorescence, and allows for extraction of the two-photon absorption cross sections. © 2014 OSA. ... Cite

Ionic self-assembly provides dense arrays of individualized, aligned single-walled carbon nanotubes.

Journal Article Angewandte Chemie (International ed. in English) · December 2013 Wrap and stack: Polyanionic [arylene]ethynylene polymers that helically wrap single-walled carbon nanotubes (SWNTs) enable the production of functionalized SWNTs that are soluble in organic solvents. These SWNTs can assemble into structures featuring align ... Full text Cite

Aqueous self-assembly of poly(ethylene oxide)-block-poly(ε-caprolactone) (PEO-b-PCL) copolymers: disparate diblock copolymer compositions give rise to nano- and meso-scale bilayered vesicles.

Journal Article Nanoscale · November 2013 Nanoparticles formed from diblock copolymers of FDA approved PEO and PCL have generated considerable interest as in vivo drug delivery vehicles. Herein, we report the synthesis of the most extensive family PEO-b-PCL copolymers that vary over the largest ra ... Full text Cite

Origins of the helical wrapping of phenyleneethynylene polymers about single-walled carbon nanotubes.

Journal Article The journal of physical chemistry. B · October 2013 The highly charged, conjugated polymer poly[p-{2,5-bis(3-propoxysulfonicacidsodiumsalt)}phenylene]ethynylene (PPES) has been shown to wrap single-wall carbon nanotubes (SWNTs), adopting a robust helical superstructure. Surprisingly, PPES adopts a helical r ... Full text Cite

The evolution of spin distribution in the photoexcited triplet state of ethyne-elaborated porphyrins.

Journal Article Chemical communications (Cambridge, England) · October 2013 Ethyne elaboration of a (porphinato)Zn(II) (PZn) chromophoric core renders fine control over the zero-field splitting (ZFS) parameters of the lowest energy photoexcited triplet state (T1), resulting in the ability to manipulate the spin distribution and es ... Full text Cite

Single-handed helical wrapping of single-walled carbon nanotubes by chiral, ionic, semiconducting polymers.

Journal Article Journal of the American Chemical Society · October 2013 We establish the requisite design for aryleneethynylene polymers that give rise to single-handed helical wrapping of single-walled carbon nanotubes (SWNTs). Highly charged semiconducting polymers that utilize either an (R)- or (S)-1,1'-bi-2-naphthol compon ... Full text Cite

Enhancement of dominant UV emission in 10 nm gallium-codoped, upconverting nanocrystals

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · September 8, 2013 Link to item Cite

Regulation of cardiac nitric oxide signaling by nuclear β-adrenergic and endothelin receptors.

Journal Article Journal of molecular and cellular cardiology · September 2013 At the cell surface, βARs and endothelin receptors can regulate nitric oxide (NO) production. β-adrenergic receptors (βARs) and type B endothelin receptors (ETB) are present in cardiac nuclear membranes and regulate transcription. The present study investi ... Full text Cite

Computational de novo design and characterization of a protein that selectively binds a highly hyperpolarizable abiological chromophore.

Journal Article Journal of the American Chemical Society · September 2013 This work reports the first example of a single-chain protein computationally designed to contain four α-helical segments and fold to form a four-helix bundle encapsulating a supramolecular abiological chromophore that possesses exceptional nonlinear optic ... Full text Cite

Raman spectroscopic investigation of individual single-walled carbon nanotubes helically wrapped by Ionic, semiconducting polymers

Journal Article Journal of Physical Chemistry C · July 18, 2013 Raman-active vibrational modes of (6,5) chirality-enriched single-walled carbon nanotubes (SWNTs), helically wrapped by semiconducting poly[2,6-{1,5-bis(3-propoxysulfonic acid sodium salt)}naphthylene]ethynylene (PNES), are described in great detail. At an ... Full text Cite

SU-E-T-106: Validation of a Nanoparticle Terminated Fiber Optic Dosimeter On 6 MV LINAC for Photon and Electron Beams in a Solid Water Phantom.

Journal Article Medical physics · June 2013 Patient safety and dose-monitoring during routine radiotherapy treatments is of paramount importance to modern and future medical procedures and subsequent care. Currently, there are few, if any, options for real time in-vivo dosimetry, necessitating the n ... Full text Cite

Exploiting plasmon-induced hot electrons in molecular electronic devices.

Journal Article ACS nano · May 2013 Plasmonic nanostructures can induce a number of interesting responses in devices. Here we show that hot electrons can be extracted from plasmonic particles and directed into a molecular electronic device, which represents a new mechanism of transfer from l ... Full text Cite

Biodegradable Polymersomes for the Delivery of Gemcitabine to Panc-1 Cells.

Journal Article Journal of pharmaceutics · January 2013 Traditional anticancer chemotherapy often displays toxic side effects, poor bioavailability, and a low therapeutic index. Targeting and controlled release of a chemotherapeutic agent can increase drug bioavailability, mitigate undesirable side effects, and ... Full text Open Access Cite

Soft biodegradable polymersomes from caprolactone-derived polymers

Journal Article Soft Matter · November 14, 2012 Polymersomes have promise for advanced theranostic delivery. We report here the design and characterization of a series of block copolymers that assemble into soft, bioresorbable, and non-toxic vesicles. The polymers are based on poly(ethylene glycol)-poly ... Full text Cite

Enhanced dispersion of CdSe/MEH-CN-PPV hybrid nanocomposites by in situ polymerization using AEM as photopolymerizable precursor

Journal Article Colloid and Polymer Science · October 1, 2012 Colloidal quantum dots (CQDs) can easily become aggregated when blended in a polymer matrix. Although several techniques have been reported to prepare dispersed CQDs in a polymer matrix, the novel approach of this work is to obtain well-dispersed CQD-polym ... Full text Cite

Dual energy converting nano-phosphors: upconversion luminescence and X-ray excited scintillation from a single composition of lanthanide-doped yttrium oxide.

Journal Article Dalton transactions (Cambridge, England : 2003) · October 2012 We report an upconverting nanomaterial composition, [Y(2)O(3); Yb (2%), Er (1%)], that converts both X-ray and high-fluence NIR irradiation to visible light. This composition is compared to a higher Yb(3+) doped composition, [Y(2)O(3); Yb (10%), Er (1%)], ... Full text Cite

Exceptional delocalization of electrons in conjugated porphyrin arrays

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · August 19, 2012 Link to item Cite

Effect of solvent polarity and electrophilicity on quantum yields and solvatochromic shifts of single-walled carbon nanotube photoluminescence.

Journal Article Journal of the American Chemical Society · August 2012 In this work, we investigate the impact of the solvation environment on single-walled carbon nanotube (SWCNT) photoluminescence quantum yield and optical transition energies (E(ii)) using a highly charged aryleneethynylene polymer. This novel surfactant pr ... Full text Cite

Quasi-ohmic single molecule charge transport through highly conjugated meso-to-meso ethyne-bridged porphyrin wires.

Journal Article Nano letters · June 2012 Understanding and controlling electron transport through functional molecules are of primary importance to the development of molecular scale devices. In this work, the single molecule resistances of meso-to-meso ethyne-bridged (porphinato)zinc(II) structu ... Full text Cite

Design of coupled porphyrin chromophores with unusually large hyperpolarizabilities

Journal Article Journal of Physical Chemistry C · May 3, 2012 Figure Persented: A new series of push-pull porphyrin-based chromophores with unusually large static first hyperpolarizabilities are designed on the basis of coupled-perturbed Hartree-Fock and density functional calculations. The proper combination of crit ... Full text Cite

Electronic transport in porphyrin supermolecule-gold nanoparticle assemblies.

Journal Article Nano letters · May 2012 Temperature-dependent transport of hybrid structures consisting of gold nanoparticle arrays functionalized by conjugated organic molecules [(4'-thiophenyl)ethynyl-terminated meso-to-meso ethyne-bridged (porphinato)zinc(II) complexes] that possess exception ... Full text Cite

Photo-responsive polymersomes and oligonucleotide assemblies

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · March 25, 2012 Link to item Cite

Acentric 2-D ensembles of D-br-A electron-transfer chromophores via vectorial orientation within amphiphilic n-helix bundle peptides for photovoltaic device applications.

Journal Article Langmuir : the ACS journal of surfaces and colloids · February 2012 We show that simply designed amphiphilic 4-helix bundle peptides can be utilized to vectorially orient a linearly extended donor-bridge-acceptor (D-br-A) electron transfer (ET) chromophore within its core. The bundle's interior is shown to provide a unique ... Full text Cite

Investigations on X-ray luminescence CT for small animal imaging.

Conference Proc SPIE Int Soc Opt Eng · 2012 X-ray Luminescence CT (XLCT) is a hybrid imaging modality combining x-ray and optical imaging in which x-ray luminescent nanophosphors (NPs) are used as emissive imaging probes. NPs are easily excited using common CT energy x-ray beams, and the NP luminesc ... Full text Link to item Cite

Composite electronic materials based on poly(3,4-propylenedioxythiophene) and highly charged poly(aryleneethynylene)-wrapped carbon nanotubes for supercapacitors.

Journal Article ACS applied materials & interfaces · January 2012 Supercapacitor charge storage media were fabricated using the semiconducting polymer poly(3,4-propylenedioxythiophene) (PProDOT) and single-walled carbon nanotubes (SWNTs) that were helically wrapped with ionic, conjugated poly[2,6-{1,5-bis(3-propoxysulfon ... Full text Cite

Sensing Membrane Stress with Near IR-Emissive Porphyrins

Conference Biophysical Journal · January 2012 Full text Cite

Controlling polarization dependent reactions to fabricate multi-component functional nanostructures

Journal Article Advanced Functional Materials · December 20, 2011 In spite of novel lithographic processes that enable new approaches to fabricating materials, directed assembly of multi-component hybrid devices remains a challenge. Ferroelectric nanolithography exploits polarization dependent surface interactions to pat ... Full text Cite

Two-photon accessed excited state absorption in bis(terpyridyl osmium)-(porphinato)zinc

Journal Article Optics InfoBase Conference Papers · December 1, 2011 Two-photon absorption properties of a (terpyridyl)osmium-(porphinato)zinc (OsPZnOs) are studied in bulk and waveguides. Integration of OsPZnOs (d>1300GM) in waveguides showed enhanced nonlinear performance and potential for photonic applications. © OSA/ CL ... Cite

Photophysics of a near IR nonlinear absorber for waveguide applications

Journal Article Optics InfoBase Conference Papers · December 1, 2011 Photophysics of a zinc porphyrin-based NIR nonlinear absorber are reported. Welloverlapped two-photon absorption and broad triplet excited state absorption result in a strong nonlinear optical response especially useful in waveguide applications. © 2011 OS ... Cite

Near IR nonlinear optics of an organic supermolecule

Journal Article Optics InfoBase Conference Papers · December 1, 2011 Two-photon accessed excited state absorption is shown to be an important mechanism in the near-IR nonlinear response of an organic supermolecule. This mechanism also provides an enhanced nonlinear absorption in an optical waveguide configuration. © 2011 OS ... Cite

Dynamics and transient absorption spectral signatures of the single-wall carbon nanotube electronically excited triplet state.

Journal Article Journal of the American Chemical Society · November 2011 We utilize femtosecond-to-microsecond time domain pump-probe transient absorption spectroscopy to interrogate for the first time the electronically excited triplet state of individualized single-wall carbon nanotubes (SWNTs). These studies exploit (6,5) ch ... Full text Cite

Near IR nonlinear absorption of an organic supermolecule [Invited]

Journal Article Optical Materials Express · November 1, 2011 The photophysics of bis(terpyridyl)osmium-(porphinato)zinc-bis(terpyridyl)osmium (OsPZnOs), a D-π-A-π-D symmetric supermolecule, were investigated in the femtosecond and nanosecond regimes. The supermolecule exhibits a two-photon absorption (δpeak ~900 GM) ... Full text Cite

Excited state contributions to near infrared nonliner optical response

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · August 28, 2011 Link to item Cite

Single-chain, helical wrapping of individualized, single-walled carbon nanotubes by ionic poly(aryleneethynylene)s: New compositions for photoinduced charge transfer reactions and photovoltaic applications

Journal Article ACS National Meeting Book of Abstracts · August 25, 2011 Amphiphilic, linear, semi-conducting aryleneethynylene polymers such as poly[p-{2,5-bis(3-propoxysulfonicacidsodiumsalt)}phenylene]ethynylene (PPES) and poly[2,6-{1,5-bis(3-propoxysulfonicacidsodiumsalt)}napthylene]ethynylene (PNES) efficiently disperse si ... Cite

Sensing membrane stress with near IR-emissive porphyrins.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · August 2011 Probes embedded within a structure can enable prediction of material behavior or failure. Carefully assembled composites that respond intelligently to physical changes within a material could be useful as intrinsic sensors. Molecular rotors are one such to ... Full text Cite

Two-photon absorption properties of proquinoidal D-A-D and A-D-A quadrupolar chromophores.

Journal Article The journal of physical chemistry. A · June 2011 We report the synthesis, one- and two-photon absorption spectroscopy, fluorescence, and electrochemical properties of a series of quadrupolar molecules that feature proquinoidal π-aromatic acceptors. These quadrupolar molecules possess either donor-accepto ... Full text Cite

Synthesis and SAR of pyrimidine-based, non-nucleotide P2Y14 receptor antagonists.

Journal Article Bioorganic & medicinal chemistry letters · May 2011 A weak antagonist of the pyrimidinergic receptor P2Y(14) containing a dihydropyridopyrimidine core was identified through high-throughput screening. Subsequent optimization led to potent, non-UTP competitive antagonists and represent the first reported non ... Full text Cite

The identification of 4,7-disubstituted naphthoic acid derivatives as UDP-competitive antagonists of P2Y14.

Journal Article Bioorganic & medicinal chemistry letters · May 2011 A weak, UDP-competitive antagonist of the pyrimidinergic receptor P2RY(14) with a naphthoic acid core was identified through high-throughput screening. Optimization provided compounds with improved potency but poor pharmacokinetics. Acylglucuronidation was ... Full text Cite

Structural and pH dependence of excited state PCET reactions involving reductive quenching of the MLCT excited state of [RuII(bpy)2(bpz)]2+ by hydroquinones.

Journal Article The journal of physical chemistry. A · April 2011 The proton-coupled electron transfer (PCET) reaction between the bpz-based photoexcited (3)MLCT state of [Ru(II)(bpy)(2)(bpz)](2+) (bpy = 2,2'-bipyridine, bpz = 2,2'-bipyrazine) and a series of substituted hydroquinones (H(2)Q) has been studied by transien ... Full text Cite

Electron transfer reactions of rigid, cofacially compressed, π-stacked porphyrin-bridge-quinone systems

Journal Article Coordination Chemistry Reviews · April 1, 2011 A 1,8-naphthyl pillaring motif can be utilized to enforce sub van der Waals interplanar separations between juxtaposed porphyryl, aromatic bridge, and quinonyl components of donor-spacer-acceptor (D-Sp-A) compounds. Such structures, synthesized via metal-m ... Full text Cite

The roles of molecular structure and effective optical symmetry in evolving dipolar chromophoric building blocks to potent octopolar nonlinear optical chromophores.

Journal Article Journal of the American Chemical Society · March 2011 A series of mono-, bis-, tris-, and tetrakis(porphinato)zinc(II) (PZn)-elaborated ruthenium(II) bis(terpyridine) (Ru) complexes have been synthesized in which an ethyne unit connects the macrocycle meso carbon atom to terpyridyl (tpy) 4-, 4'-, and 4''-posi ... Full text Cite

Difluoroethylamines as an amide isostere in inhibitors of cathepsin K.

Journal Article Bioorganic & medicinal chemistry letters · February 2011 The trifluoroethylamine group found in cathepsin K inhibitors like odanacatib can be replaced by a difluoroethylamine group. This change increased the basicity of the nitrogen which positively impacted the log D. This translated into an improved oral bioav ... Full text Cite

Photophysics of a near IR nonlinear absorber for waveguide applications

Conference Optics InfoBase Conference Papers · January 1, 2011 Photophysics of a zinc porphyrin-based NIR nonlinear absorber are reported. Welloverlapped two-photon absorption and broad triplet excited state absorption result in a strong nonlinear optical response especially useful in waveguide applications. © 2011 OS ... Full text Cite

Effects of Membrane Rheology on Leuko-polymersome Adhesion to Inflammatory Ligands.

Journal Article Soft matter · January 2011 A strategy for treating inflammatory disease is to create micro-particles with the adhesive properties of leukocytes. The underlying rheology of deformable adhesive microspheres would be an important factor in the adhesive performance of such particles. In ... Full text Cite

Two-photon accessed excited state absorption in bis(terpyridyl osmium)-(porphinato)zinc

Journal Article 2011 Conference on Lasers and Electro-Optics: Laser Science to Photonic Applications, CLEO 2011 · January 1, 2011 Two-photon absorption properties of a (terpyridyl)osmium-(porphinato)zinc (OsPZnOs) are studied in bulk and waveguides. Integration of OsPZnOs (δ>1300GM) in waveguides showed enhanced nonlinear performance and potential for photonic applications. © 2011 OS ... Full text Cite

Excitation of highly conjugated (porphinato)palladium(II) and (porphinato)platinum(II) oligomers produces long-lived, triplet states at unit quantum yield that absorb strongly over broad spectral domains of the NIR.

Journal Article The journal of physical chemistry. B · November 2010 Transient dynamical studies of bis[(5,5'-10,20-bis(2,6-bis(3,3-dimethylbutoxy)phenyl)porphinato)palladium(II)]ethyne (PPd(2)), 5,15-bis{[(5'-10,20-bis(2,6-bis(3,3-dimethylbutoxy)phenyl)porphinato)palladium(II)]ethynyl}(10,20-bis(2,6-bis(3,3-dimethylbutoxy) ... Full text Open Access Cite

De novo design and molecular assembly of a transmembrane diporphyrin-binding protein complex.

Journal Article Journal of the American Chemical Society · November 2010 The de novo design of membrane proteins remains difficult despite recent advances in understanding the factors that drive membrane protein folding and association. We have designed a membrane protein PRIME (PoRphyrins In MEmbrane) that positions two non-na ... Full text Open Access Cite

Analysis of the unusual wavelength dependence of the first hyperpolarizability of porphyrin derivatives

Journal Article Proceedings of SPIE - The International Society for Optical Engineering · October 22, 2010 Successfully predicting the frequency dispersion of electronic hyperpolarizabilities is an unresolved challenge in materials science and electronic structure theory. It has been shown1 that the generalized Thomas-Kuhn sum rules combined with linear absorpt ... Full text Cite

Phase transfer catalysts drive diverse organic solvent solubility of single-walled carbon nanotubes helically wrapped by ionic, semiconducting polymers.

Journal Article Nano letters · October 2010 Use of phase transfer catalysts such as 18-crown-6 enables ionic, linear conjugated poly[2,6-{1,5-bis(3-propoxysulfonicacidsodiumsalt)}naphthylene]ethynylene (PNES) to efficiently disperse single-walled carbon nanotubes (SWNTs) in multiple organic solvents ... Full text Open Access Cite

Supermolecular-chromophore-sensitized near-infrared-to-visible photon upconversion.

Journal Article Journal of the American Chemical Society · October 2010 Selective near-IR (NIR) excitation (780 nm) of the conjugated supermolecule ruthenium(II) [15-(4'-ethynyl-(2,2';6',2''-terpyridinyl))-bis[(5,5',-10,20-di(2',6'-bis(3,3-dimethylbutoxy)phenyl)porphinato)zinc(II)]ethyne][4'-pyrrolidin-1-yl-2,2';6',2''-terpyri ... Full text Open Access Cite

Tunable leuko-polymersomes that adhere specifically to inflammatory markers.

Journal Article Langmuir : the ACS journal of surfaces and colloids · September 2010 The polymersome, a fully synthetic cell mimetic, is a tunable platform for drug delivery vehicles to detect and treat disease (theranostics). Here, we design a leuko-polymersome, a polymersome with the adhesive properties of leukocytes, which can effective ... Full text Cite

Novel, lanthanide-based nanoparticles for NIR to UV energy conversion

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · August 22, 2010 Link to item Cite

A Generalized System for Photo-Responsive Membrane Rupture in Polymersomes.

Journal Article Advanced functional materials · August 2010 Polymersomes are vesicles whose membranes are comprised of self-assembled block co-polymers. We recently showed that co-encapsulating conjugated multi-porphyrin dyes in a polymersome membrane with ferritin protein in the aqueous lumen confers photo-labilit ... Full text Cite

Control of the orientational order and nonlinear optical response of the "push-pull" chromophore RuPZn via specific incorporation into densely packed monolayer ensembles of an amphiphilic four-helix bundle peptide: characterization of the peptide-chromophore complexes.

Journal Article Journal of the American Chemical Society · August 2010 "Push-pull" chromophores based on extended pi-electron systems have been designed to exhibit exceptionally large molecular hyperpolarizabilities. We have engineered an amphiphilic four-helix bundle peptide to vectorially incorporate such hyperpolarizable c ... Full text Open Access Cite

Control of the orientational order and nonlinear optical response of the "push-pull" chromophore RuPZn via specific incorporation into densely packed monolayer ensembles of an amphiphilic 4-helix bundle peptide: second harmonic generation at high chromophore densities.

Journal Article Journal of the American Chemical Society · July 2010 The macroscopic nonlinear optical response of the "push-pull" chromophore RuPZn incorporated into a single monolayer of the amphiphilic 4-helix bundle peptide (AP0) covalently attached to a solid substrate at high in-plane density has been measured. The se ... Full text Cite

Optimizing single-molecule conductivity of conjugated organic oligomers with carbodithioate linkers.

Journal Article Journal of the American Chemical Society · June 2010 In molecular electronics, the linker group, which attaches the functional molecular core to the electrode, plays a crucial role in determining the overall conductivity of the molecular junction. While much focus has been placed on optimizing molecular core ... Full text Open Access Cite

Plasmon enhanced photoconduction in porphyrin-gold nanoparticle assemblies for photovoltaic applications

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · March 21, 2010 Link to item Cite

Computational design and elaboration of a de novo heterotetrameric alpha-helical protein that selectively binds an emissive abiological (porphinato)zinc chromophore.

Journal Article Journal of the American Chemical Society · March 2010 The first example of a computationally de novo designed protein that binds an emissive abiological chromophore is presented, in which a sophisticated level of cofactor discrimination is pre-engineered. This heterotetrameric, C(2)-symmetric bundle, A(His):B ... Full text Open Access Cite

The discovery of MK-0674, an orally bioavailable cathepsin K inhibitor.

Journal Article Bioorganic & medicinal chemistry letters · February 2010 MK-0674 is a potent and selective cathepsin K inhibitor from the same structural class as odanacatib with a comparable inhibitory potency profile against Cat K. It is orally bioavailable and exhibits long half-life in pre-clinical species. In vivo studies ... Full text Cite

Plasmon-induced electrical conduction in molecular devices.

Journal Article ACS nano · February 2010 Metal nanoparticles (NPs) respond to electromagnetic waves by creating surface plasmons (SPs), which are localized, collective oscillations of conduction electrons on the NP surface. When interparticle distances are small, SPs generated in neighboring NPs ... Full text Open Access Cite

Tunable Leuko-polymersomes That Adhere Specifically to Inflammatory Markers

Other · 2010 The polymersome, a fully synthetic cell mimetic, is a tunable platform for drug delivery vehicles to detect and treat disease (theranostics). Here, we design a leuko-polymersome, a polymersome with the adhesive properties of leukocytes, which can effective ... Full text Open Access Cite

Probing polarization and dielectric function of molecules with higher order harmonics in scattering-near-field scanning optical microscopy

Journal Article Journal of Applied Physics · December 28, 2009 The idealized system of an atomically flat metallic surface [highly oriented pyrolytic graphite (HOPG)] and an organic monolayer (porphyrin) was used to determine whether the dielectric function and associated properties of thin films can be accessed with ... Full text Open Access Cite

In vivo dendritic cell tracking using fluorescence lifetime imaging and near-infrared-emissive polymersomes.

Journal Article Molecular imaging and biology · May 2009 PurposeNoninvasive in vivo cell-tracking techniques are necessary to advance the field of cellular-based therapeutics as well as to elucidate mechanisms governing in vivo cell biology. Fluorescence is commonly used for in vitro and postmortem biom ... Full text Cite

Helical wrapping of single-walled carbon nanotubes by water soluble poly(p-phenyleneethynylene).

Journal Article Nano letters · April 2009 Amphiphilic, linear conjugated poly[p-{2,5-bis(3-propoxysulfonicacidsodiumsalt)}phenylene]ethynylene (PPES) efficiently disperses single-walled carbon nanotubes (SWNTs) under ultrasonication conditions into the aqueous phase. Vis-NIR absorption spectroscop ... Full text Cite

Physical chemistry: How to improve your image.

Journal Article Nature · April 2009 Full text Cite

One- and two-photon absorption of highly conjugated multiporphyrin systems in the two-photon Soret transition region.

Journal Article The Journal of chemical physics · April 2009 This study presents a detailed investigation of near-infrared one- and two-photon absorption (TPA) in a series of highly conjugated (porphinato)zinc(II) compounds. The chromophores interrogated include meso-to-meso ethyne-bridged (porphinato)zinc(II) oligo ... Full text Cite

Incorporating abiological function in de novo designed proteins

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · March 22, 2009 Link to item Cite

Light induced destruction of polymersome/porphyrin/ferritin composite membranes

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · March 22, 2009 Link to item Cite

Photoinitiated destruction of composite porphyrin-protein polymersomes.

Journal Article Journal of the American Chemical Society · March 2009 Bilayer vesicles assembled from amphiphilic diblock copolymers (polymersomes) adopt asymmetric structures when loaded with moderate concentrations (>or=1.5 mg/mL) of horse spleen ferritin (HSF) or its iron-free variant (HSAF). Incorporation of both ferriti ... Full text Cite

In vivo fluorescence imaging: a personal perspective.

Journal Article Wiley interdisciplinary reviews. Nanomedicine and nanobiotechnology · March 2009 In vivo fluorescence imaging with near-infrared (NIR) light holds enormous potential for a wide variety of molecular diagnostic and therapeutic applications. Because of its quantitative sensitivity, inherent biological safety, and relative ease of use (i.e ... Full text Cite

Portable UV-visible spectrometer for measuring absorbance and dichroism of Langmuir monolayers at air-water interfaces.

Journal Article The Review of scientific instruments · March 2009 An UV-visible spectrometer for measuring absorbance and dichroism of Langmuir monolayers under in situ conditions is described. The spectrometer utilizes a stand-alone multipass sensor, which is placed in a Langmuir trough and coupled with light source and ... Full text Cite

Composite electronic materials for supercapacitor applications

Journal Article ECS Transactions · January 1, 2009 The polyanionic, poly(aryleneethynylene) polymer PNES that helically wraps single-walled carbon nanotubes (SWNTs) was used in a variety of novel electrically active composites, combined with the electroactive polymer poly(3,4-propylenedioxythiophene) PProD ... Full text Cite

Evaluation of composite electronic materials based upon single-wall carbon nanotubes and highly charged poly(aryleneethynylene)s for supercapacitor applications

Journal Article ECS Transactions · January 1, 2009 Although substantial improvement in capacitance, energy densities, and discharge times has been achieved for redox supercapacitors over the last several years, important challenges remain. These include high series resistance which limits the ability to qu ... Full text Cite

Fully bioresorbable polymeric vesicles for therapeutic applications

Journal Article AIChE Annual Meeting, Conference Proceedings · December 1, 2008 Cite

Hyper-Rayleigh scattering for solution phase structure determination

Journal Article Proceedings of SPIE - The International Society for Optical Engineering · November 12, 2008 Hyper-Rayleigh scattering (HRS) is the only second-order nonlinear optical (NLO) technique allowed in an isotropic solution. Being an even-order technique, it is sensitive to (non-centro)symmetry. Therefore, HRS is a unique tool to determine solution-phase ... Full text Cite

Molecular design of porphyrin-based nonlinear optical materials.

Journal Article The journal of physical chemistry. A · November 2008 Nonlinear optical chromophores containing (porphyrinato)Zn(II), proquinoid, and (terpyridyl)metal(II) building blocks were optimized in a library containing approximately 10(6) structures using the linear combination of atomic potentials (LCAP) methodology ... Full text Cite

Identification of a nonbasic, nitrile-containing cathepsin K inhibitor (MK-1256) that is efficacious in a monkey model of osteoporosis.

Journal Article Journal of medicinal chemistry · October 2008 Herein, we report on the identification of nonbasic, potent, and highly selective, nitrile-containing cathepsin K (Cat K) inhibitors that are built on our previously identified cyclohexanecarboxamide core structure. Subsequent to our initial investigations ... Full text Cite

Synthesis and self-assembly of biodegradable polyethylene oxide-b-polycaprolactone (PEO-A-PCL) diblock copolymers

Journal Article Technical Proceedings of the 2008 NSTI Nanotechnology Conference and Trade Show, NSTI-Nanotech, Nanotechnology 2008 · October 1, 2008 A series of amphiphilic poly(ethylene oxide)-b-polycaprolactone (PEO-b-PCL) diblock copolymers had been synthesized by ring-opening or sequential anionic living polymerization. Nuclear Magnetic Resonance (NMR) and gel permeation chromatography (GPC) were u ... Cite

Using alpha-helical coiled-coils to design nanostructured metalloporphyrin arrays.

Journal Article Journal of the American Chemical Society · September 2008 We have developed a computational design strategy based on the alpha-helical coiled-coil to generate modular peptide motifs capable of assembling into metalloporphyrin arrays of varying lengths. The current study highlights the extension of a two-metallopo ... Full text Cite

Polymersomes: a new multi-functional tool for cancer diagnosis and therapy.

Journal Article Methods (San Diego, Calif.) · September 2008 Nanoparticles are being developed as delivery vehicles for therapeutic pharmaceuticals and contrast imaging agents. Polymersomes (mesoscopic polymer vesicles) possess a number of attractive biomaterial properties that make them ideal for these applications ... Full text Cite

POLY 512-Charge transport properties of solution processable (porphinato)zinc(II) ethynylenes

Conference ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY · August 17, 2008 Link to item Cite

Ultrafast excited-state dynamics of nanoscale near-infrared emissive polymersomes.

Journal Article Journal of the American Chemical Society · July 2008 Formed through cooperative self-assembly of amphiphilic diblock copolymers and electronically conjugated porphyrinic near-infrared (NIR) fluorophores (NIRFs), NIR-emissive polymersomes (50 nm to 50 microm diameter polymer vesicles) define a family of organ ... Full text Cite

Discovery of [(3-bromo-7-cyano-2-naphthyl)(difluoro)methyl]phosphonic acid, a potent and orally active small molecule PTP1B inhibitor.

Journal Article Bioorganic & medicinal chemistry letters · June 2008 A series of quinoline/naphthalene-difluoromethylphosphonates were prepared and were found to be potent PTP1B inhibitors. Most of these compounds bearing polar functionalities or large lipophilic residues did not show appreciable oral bioavailability in rod ... Full text Cite

Synthesis of water-soluble poly(p-phenyleneethynylene) in neat water under aerobic conditions via Suzuki-Miyaura polycondensation using a diborylethyne synthon.

Journal Article Organic letters · April 2008 We report the synthesis, structure, and characterization of a novel ethyne synthon, 1,2-bis(4',4',5',5'-tetramethyl[1',3',2']dioxaborolan-2'-yl)ethyne (B2C2). We demonstrate the utility of B2C2 in the Suzuki-Miyaura polycondensation reaction, synthesizing ... Full text Cite

Substituted 2,2-bisaryl-bicycloheptanes as novel and potent inhibitors of 5-lipoxygenase activating protein.

Journal Article Bioorganic & medicinal chemistry letters · March 2008 The discovery and SAR of a novel series of substituted 2,2-bisaryl-bicycloheptane inhibitors of 5-lipoxygenase activating protein (FLAP) are herein described. SAR studies have shown that 2,5-substitution on the exo-aryl group is optimal for potency. The mo ... Full text Cite

The discovery of odanacatib (MK-0822), a selective inhibitor of cathepsin K.

Journal Article Bioorganic & medicinal chemistry letters · February 2008 Odanacatib is a potent, selective, and neutral cathepsin K inhibitor which was developed to address the metabolic liabilities of the Cat K inhibitor L-873724. Substituting P1 and modifying the P2 side chain led to a metabolically robust inhibitor with a lo ... Full text Cite

Structure and dynamics of an extended conjugated NLO chromophore within an amphiphilic 4-helix bundle peptide by molecular dynamics simulation.

Journal Article The journal of physical chemistry. B · February 2008 Incorporation of extended conjugated chromophores into amphiphilic 4-helix bundle peptides has been shown experimentally to be an effective means to orient the chromphores vectorially in 2-D ensembles with high in-plane density. The designed microscopic hy ... Full text Cite

The effect of molecular orientation on the potential of porphyrin-metal contacts.

Journal Article Nano letters · January 2008 The effect of molecular orientation at metal contacts on interface properties was determined by examining the local work function of porphyrin on atomically smooth graphite. The orientation was varied by self-assembly from the vapor phase, and the local po ... Full text Cite

Leuko-polymersomes.

Journal Article Faraday discussions · January 2008 Polymersomes are vesicles whose membranes are comprised of self-assembled amphiphilic block co-polymers. Synthetic control of block co-polymer chemistry provides an advantageous diversity of polymersome functions, ranging from tunable materials strength, s ... Full text Cite

Modulation of dark conductivity over a 1 × 10-12 to 1 × 10-5 S/cm range through ancillary group modification in amorphous solids of ethyne-bridged (porphinato)zinc(II) oligomers

Journal Article Chemistry of Materials · December 11, 2007 Modulation of dark conductivity (DC) over a 1 × 10-12 to 1 × 10-5 S/cm range through ancillary group modification in amorphous solids of ethylene-bridged (Prophinato)zinc (II) (PZn n)oligomers was analyzed. Results from atomic absorption spectroscopy show ... Full text Cite

De novo design of a single-chain diphenylporphyrin metalloprotein.

Journal Article Journal of the American Chemical Society · September 2007 We describe the computational design of a single-chain four-helix bundle that noncovalently self-assembles with fully synthetic non-natural porphyrin cofactors. With this strategy, both the electronic structure of the cofactor as well as its protein enviro ... Full text Cite

Molecular engineering of intensely near-infrared absorbing excited states in highly conjugated oligo(porphinato)zinc-(polypyridyl)metal(II) supermolecules.

Journal Article Journal of the American Chemical Society · August 2007 A new series of chromophores, MPZn(n), which combine ethyne-bridged bis(terpyridyl)metal(II)-(porphinato)zinc(II) (MPZ(n)) and oligomeric, ethyne-bridged (porphinato)zinc(II) (PZn(n)) architectures, have been synthesized and characterized, along with a ser ... Full text Cite

Carbodithioate-terminated oligo(phenyleneethynylene)s: synthesis and surface functionalization of gold nanoparticles.

Journal Article Organic letters · July 2007 Carbodithioate-terminated bis(phenylene)ethynylenes and oligo(phenyleneethynylene)s have been synthesized from TMSE-protected 4-iododithiobenzoic acid ester (1) and 4-ethynyldithiobenzoic acid ester (3) via Pd-catalyzed cross-coupling reactions. TEM and sp ... Full text Cite

Temperature-dependent mechanistic transition for photoinduced electron transfer modulated by excited-state vibrational relaxation dynamics.

Journal Article The journal of physical chemistry. B · June 2007 The electron transfer (ET) dynamics of an unusually rigid pi-stacked (porphinato)zinc(II)-spacer-quinone (PZn-Q) system, [5-[8'-(4' '-[8' ''-(2' '' ',5' '' '-benzoquinonyl)-1' ''-naphthyl]-1' '-phenyl)-1'-naphthyl]-10,20-diphenylporphinato]zinc(II) (2a-Zn) ... Full text Cite

Pharmacokinetic assessment of a polymersome-based molecular beacon by in vivo fluorescence monitoring

Journal Article Progress in Biomedical Optics and Imaging - Proceedings of SPIE · April 30, 2007 Full text Cite

Controlling Bulk Optical Properties of Emissive Polymersomes Through Intramembranous Polymer-Fluorophore Interactions.

Journal Article Chemistry of materials : a publication of the American Chemical Society · March 2007 Interdisciplinary investigation at the interface of chemistry, engineering, and medicine has enabled the development of self-assembled nanomaterials with novel biochemical and electro-optical properties. We have recently shown that emissive polymersomes, p ... Full text Cite

Tat-functionalized near-infrared emissive polymersomes for dendritic cell labeling.

Journal Article Bioconjugate chemistry · January 2007 Dendritic cells (DCs) play a pivotal role in both immune tolerance and the initiation of immunological responses. The ability to track DCs in vivo is imperative for the development of DC-based cellular therapies and to advance our understanding of DC funct ... Full text Cite

Electronic modulation of hyperpolarizable (porphinato)zinc(II) chromophores featuring ethynylphenyl-, ethynylthiophenyl-, ethynylthiazolyl-, and ethynylbenzothiazolyl-based electron-donating and -accepting moieties.

Journal Article Inorganic chemistry · November 2006 A series of conjugated (porphinato)zinc(II)-based chromophores structurally related to [5-(4-dimethylaminophenylethynyl)-15-(5-nitrothienyl-2-ethynyl)-10,20-bis(3,5-bis(3,3-dimethyl-1-butyloxy)phenyl)]zinc(II) were synthesized using metal-catalyzed cross-c ... Full text Cite

Structural studies of amphiphilic 4-helix bundle peptides incorporating designed extended chromophores for nonlinear optical biomolecular materials.

Journal Article Nano letters · November 2006 Extended conjugated chromophores containing (porphinato)zinc components that exhibit large optical polarizabilities and hyperpolarizabiliites are incorporated into amphiphilic 4-helix bundle peptides via specific axial histidyl ligation of the metal. The b ... Full text Cite

Incorporation of designed extended chromophores into amphiphilic 4-helix bundle peptides for nonlinear optical biomolecular materials.

Journal Article Nano letters · November 2006 Multipigment ensembles that feature (porphinato)metal components and appropriate ethyne- and oligoyne-based chromophore-to-chromophore connectivity can manifest large optical polarizabilities and hyperpolarizabilities by design. Their vectorial orientation ... Full text Cite

Quantitative membrane loading of polymer vesicles.

Journal Article Soft matter · October 2006 We utilize a series of structurally homologous, multi-porphyrin-based, fluorophores (PBFs) in order to explore the capacity of polymer vesicles (polymersomes) to stably incorporate large hydrophobic molecules, non-covalently within their thick lamellar mem ... Full text Cite

Ethyne-bridged (porphinato)zinc(II)-(porphinato)iron(III) complexes: phenomenological dependence of excited-state dynamics upon (porphinato)iron electronic structure.

Journal Article Journal of the American Chemical Society · August 2006 We report the synthesis, spectroscopy, potentiometric properties, and excited-state dynamical studies of 5-[(10,20-di-((4-ethyl ester)methylene-oxy)phenyl)porphinato]zinc(II)-[5'-[(10',20'- di-((4-ethyl ester)methylene-oxy)phenyl)porphinato]iron(III)-chlor ... Full text Cite

One-dimensional diffusion-limited relaxation of photoexcitations in suspensions of single-walled carbon nanotubes

Journal Article Physical Review B - Condensed Matter and Materials Physics · August 1, 2006 We report pump-probe transient absorption spectroscopy on carbon nanotubes with a high initial excitation density. We find that the recovery of the ground state optical absorption is well described by a 1 t relaxation, indicating that the long time populat ... Full text Cite

Exceptional near-infrared fluorescence quantum yields and excited-state absorptivity of highly conjugated porphyrin arrays.

Journal Article Journal of the American Chemical Society · July 2006 We show that meso-to-meso ethyne-bridged (porphinato)zinc(II) oligomers (PZnn structures) define exceptional low band gap organic materials that possess both large magnitude NIR S1 --> S0 fluorescence quantum yields and substantial S1 --> Sn absorptive cro ... Full text Cite

Conjugated chromophore arrays with unusually large hole polaron delocalization lengths.

Journal Article Journal of the American Chemical Society · July 2006 We report variable temperature X-band EPR spectroscopic data for the cation radical states of meso-to-meso ethyne-bridged (porphinato)zinc(II) (PZnn) oligomers. These [PZn2-PZn7]+ species span an average 18-75 A length scale and display peak-to-peak EPR li ... Full text Cite

Identification of a potent and selective non-basic cathepsin K inhibitor.

Journal Article Bioorganic & medicinal chemistry letters · April 2006 Based on our previous study with trifluoroethylamine as a P2-P3 amide isostere of cathepsin K inhibitor, further optimization led to identification of compound 22 (L-873724) as a potent and selective non-basic cathepsin K inhibitor. This compound showed ex ... Full text Cite

Conformation-assisted inhibition of protein-tyrosine phosphatase-1B elicits inhibitor selectivity over T-cell protein-tyrosine phosphatase.

Journal Article The Journal of biological chemistry · March 2006 PTP-1B represents an attractive target for the treatment of type 2 diabetes and obesity. Given the role that protein phosphatases play in the regulation of many biologically relevant processes, inhibitors against PTP-1B must be not only potent, but also se ... Full text Cite

Enzyme occupancy measurement of intracellular protein tyrosine phosphatase 1B using photoaffinity probes.

Journal Article Analytical biochemistry · February 2006 Protein tyrosine phosphatase 1B (PTP1B) is believed to be one of the enzymes involved in down-regulating the insulin receptor and is a drug target for the treatment of type II diabetes. To better understand the in vitro and in vivo behavior of PTP1B inhibi ... Full text Cite

Nonlinear transmission of highly conjugated (polypyridyl)metal-(porphinato)zinc(II) compounds

Journal Article Optics InfoBase Conference Papers · January 1, 2006 Several materials that have been demonstrated to have very large excited state NIR absorption coefficients have been examined by nanosecond Z-scan and nonlinear transmission experiments and demonstrate large decreases in transmission with increasing fluenc ... Cite

Coordination compounds for functional nonlinear optics: Enhancing and switching the second-order nonlinear optical responses

Journal Article ACS Symposium Series · January 1, 2006 In this work, we describe the second-order nonlinear optical (NLO) properties of a number of chromophores that feature transition metal ions in classic coordination environments. We focused our attention on the advantages of diese species over standard hyp ... Full text Cite

Broad spectral domain fluorescence wavelength modulation of visible and near-infrared emissive polymersomes.

Journal Article Journal of the American Chemical Society · November 2005 Incorporation of an extended family of multi[(porphinato)zinc(II)] (PZn)-based supermolecular fluorophores into the lamellar membranes of polymersomes (50 nm to 50 mum diameter polymer vesicles) gives rise to electrooptically diverse nano-to-micron (meso) ... Full text Cite

Amphiphilic four-helix bundle peptides designed for light-induced electron transfer across a soft interface.

Journal Article Nano letters · September 2005 A family of four-helix bundle peptides were designed to be amphiphilic, possessing distinct hydrophilic and hydrophobic domains along the length of the bundle's exterior. This facilitates their vectorial insertion across a soft interface between polar and ... Full text Cite

Generalized Mulliken-Hush analysis of electronic coupling interactions in compressed pi-stacked porphyrin-bridge-quinone systems.

Journal Article Journal of the American Chemical Society · August 2005 Donor-acceptor interactions were investigated in a series of unusually rigid, cofacially compressed pi-stacked porphyrin-bridge-quinone systems. The two-state generalized Mulliken-Hush (GMH) approach was used to compute the coupling matrix elements. The th ... Full text Cite

Design, synthesis, linear, and nonlinear optical properties of conjugated (porphinato)zinc(II)-based donor-acceptor chromophores featuring nitrothiophenyl and nitrooligothiophenyl electron-accepting moieties.

Journal Article Journal of the American Chemical Society · July 2005 An extensive series of conjugated (porphinato)zinc(II)-based chromophores featuring nitrothiophenyl and nitrooligothiophenyl electron-accepting moieties has been synthesized using metal-catalyzed cross-coupling reactions involving [5-bromo-15-triisopropyls ... Full text Cite

Near-infrared optical imaging of B16 melanoma cells via low-density lipoprotein-mediated uptake and delivery of high emission dipole strength tris[(porphinato)zinc(II)] fluorophores.

Journal Article Bioconjugate chemistry · May 2005 Meso-to-meso ethyne-bridged tris[(porphinato)zinc(II)] (PZn(3)) near-infrared (NIR) fluorophores (lambda(em)(max) approximately 800 nm) can be rendered sufficiently amphiphilic to enable their facile incorporation into the hydrophobic core of the apo form ... Full text Cite

Potentiometric, electronic structural, and ground- and excited-state optical properties of conjugated bis[(porphinato)zinc(II)] compounds featuring proquinoidal spacer units.

Journal Article Journal of the American Chemical Society · April 2005 We report the synthesis, optical, electrochemical, electronic structural, and transient optical properties of conjugated (porphinato)zinc(II)-spacer-(porphinato)zinc(II) (PZn-Sp-PZn) complexes that possess intervening conjugated Sp structures having varyin ... Full text Cite

Controlled fabrication of nanogaps in ambient environment for molecular electronics 043109

Journal Article Applied Physics Letters · February 24, 2005 We have developed a controlled and highly reproducible method of making nanometer-spaced electrodes using electromigration in ambient lab conditions. This advance will make feasible single molecule measurements of macromolecules with tertiary and quaternar ... Full text Cite

Near-infrared-emissive polymersomes: self-assembled soft matter for in vivo optical imaging.

Journal Article Proceedings of the National Academy of Sciences of the United States of America · February 2005 We demonstrate that synthetic soft materials can extend the utility of natural vesicles, from predominantly hydrophilic reservoirs to functional colloidal carriers that facilitate the biomedical application of large aqueous-insoluble compounds. Near-infrar ... Full text Cite

Computational de novo design and characterization of a four-helix bundle protein that selectively binds a nonbiological cofactor.

Journal Article Journal of the American Chemical Society · February 2005 We report the complete de novo design of a four-helix bundle protein that selectively binds the nonbiological DPP-Fe(III) metalloporphyrin cofactor (DPP-Fe(III) = 5, 15-Di[(4-carboxymethyleneoxy)phenyl]porphinato iron(III)). A tetrameric, D2-symmetric back ... Full text Cite

Nonlinear transmission of highly conjugated (polypyridyl)metal-(porphinato)zinc(II) compounds

Journal Article Optics InfoBase Conference Papers · January 1, 2005 Several materials that have been demonstrated to have very large excited state NIR absorption coefficients have been examined by nanosecond Z-scan and nonlinear transmission experiments and demonstrate large decreases in transmission with increasing fluenc ... Cite

Nonlinear transmission of highly conjugated (polypyridyl)metal-(porphinato)zinc(II) compounds

Journal Article 2005 Conference on Lasers and Electro-Optics, CLEO · January 1, 2005 Several materials that have been demonstrated to have very large excited state NIR absorption coefficients have been examined by nanosecond Z-scan and nonlinear transmission experiments and demonstrate large decreases in transmission with increasing fluenc ... Full text Cite

Visible and near-infrared excited-state dynamics of single-walled carbon nanotubes

Journal Article Applied Physics A: Materials Science and Processing · November 1, 2004 Excited-state lifetimes of isolated single-walled semiconducting carbon nanotubes (SWNTs) have been measured for the first time; these excited states, observed over the 400- to 1800-nm spectral domain, possess lifetimes that range from several ps to more t ... Full text Cite

Impact of electronic asymmetry on photoexcited triplet-state spin distributions in conjugated porphyrin oligomers probed via EPR spectroscopy

Journal Article Journal of Physical Chemistry B · August 12, 2004 The photophysics of triplet excitons in a series of electronically asymmetric "push-pull" π-conjugated meso-to-meso ethyne-bridged (porphinato)metal oligomers, along with electronically symmetric analogues, were studied by X-band electron paramagnetic reso ... Full text Cite

Highly conjugated (polypyridyl)metal-(porphinato)zinc(II) compounds: long-lived, high oscillator strength, excited-state absorbers having exceptional spectral coverage of the near-infrared.

Journal Article Journal of the American Chemical Society · August 2004 Transient dynamical studies of ruthenium(II) [5-(4'-ethynyl-(2,2';6',2' '-terpyridinyl))-10,20-bis(2',6'-bis(3,3-dimethyl-1-butyloxy)phenyl)porphinato]zinc(II)-(2,2';6',2' '-terpyridine)2+ bis-hexafluorophosphate (Ru-PZn), osmium(II) [5-(4'-ethynyl-(2,2';6 ... Full text Cite

Synthesis of a novel peptidic photoaffinity probe for the PTP-1B enzyme.

Journal Article Bioorganic & medicinal chemistry letters · May 2004 The synthesis of a novel radioactive peptidic photoaffinity probe for the PTP-1B enzyme as well as some SAR leading to the choice of this compound as a photoaffinity probe are presented. ... Full text Cite

The degree of charge transfer in ground and charge-separated states revealed by ultrafast visible pump/mid-IR probe spectroscopy.

Journal Article Journal of the American Chemical Society · April 2004 We demonstrate a new femtosecond visible pump/mid-IR probe spectroscopic approach to assess directly the ground- and excited-state degrees of charge transfer (CT) in donor-spacer-acceptor (D-Sp-A) structures. Two classes of (porphinato)zinc(II) (PZn)-based ... Full text Cite

Interrogating conformationally dependent electron-transfer dynamics via ultrafast visible pump/IR probe spectroscopy.

Journal Article Journal of the American Chemical Society · March 2004 We demonstrate for the first time the utility of time-resolved visible pump/mid-infrared (IR) probe spectroscopy to interrogate directly, and provide unique infomation regarding, conformationally dependent photoinduced ET dynamics and the subsequent struct ... Full text Cite

Structure based design of a series of potent and selective non peptidic PTP-1B inhibitors.

Journal Article Bioorganic & medicinal chemistry letters · February 2004 A series of benzotriazole phenyldifluoromethylphosphonic acids were found to be potent PTP-1B inhibitors. Molecular modeling on the X-ray crystal structure of the lead structure led to the design of potent PTP-1B inhibitors that show moderate selectivity a ... Full text Cite

The structural basis for the selectivity of benzotriazole inhibitors of PTP1B.

Journal Article Biochemistry · October 2003 Protein tyrosine phosphatase 1B (PTP1B) has been implicated in the regulation of the insulin signaling pathway and represents an attractive target for the design of inhibitors in the treatment of type 2 diabetes and obesity. Inspection of the structure of ... Full text Cite

Near-infrared electroluminescent light-emitting devices based on ethyne-bridged porphyrin fluorophores

Journal Article Advanced Materials · August 5, 2003 The ethyne-bridged porphyrin oligomers constitutes a highly promising new class of emissive dopants suitable for the fabrication of near infrared (NIR) polymer-based light-emitting diodes (LEDs). These fluorophores, synthesized from simple porphyrinic buil ... Full text Cite

Synthesis, electronic structure, and electron transfer dynamics of (Aryl)ethynyl-bridged donor-acceptor systems.

Journal Article Journal of the American Chemical Society · July 2003 The ET dynamics of a series of donor-spacer-acceptor (D-Sp-A) systems featuring (porphinato)zinc(II), (aryl)ethynyl bridge, and arene diimide units were investigated by pump-probe transient absorption spectroscopy. Analysis of these data within the context ... Full text Cite

3,4-Diaryl-5-hydroxyfuranones: highly selective inhibitors of cyclooxygenase-2 with aqueous solubility.

Journal Article Bioorganic & medicinal chemistry letters · March 2003 The introduction of a hydroxyl group into the 5-position of the diaryl furanone system provides highly selective inhibitors of cyclooxygenase-2. These molecules can be converted into their sodium salts which are water soluble, facilitating intravenous form ... Full text Cite

Ultrafast singlet excited-state polarization in electronically asymmetric ethyne-bridged bis[(porphinato)zinc(II)] complexes.

Journal Article Journal of the American Chemical Society · March 2003 The excited-state dynamics of two conjugated bis[(porphinato)zinc(II)] (bis[PZn]) species, bis[(5,5'-10,20-bis[3,5-bis(3,3-dimethyl-1-butyloxy)phenyl]porphinato)zinc(II)]ethyne (DD) and [(5,-10,20-bis[3,5-bis(3,3-dimethyl-1-butyloxy)phenyl]porphinato)zinc( ... Full text Cite

Pyridazinones as selective cyclooxygenase-2 inhibitors.

Journal Article Bioorganic & medicinal chemistry letters · February 2003 Pyridazinone was found to be an excellent core template for selective COX-2 inhibitors. Two potent, selective and orally active COX-2 inhibitors, which were highly efficacious in rat paw edema and rat pyresis models, have been obtained. ... Full text Cite

The Effect of Electronic Structure on Molecular First Hyperpolarizabilities of Highly Conjugated (Polypyridyl)metal-(Porphinato)zinc(II) Chromophores

Journal Article Proceedings of SPIE - The International Society for Optical Engineering · January 1, 2003 Electronic structural modifications of previously reported highly conjugated (polypyridyl)metal-(porphinato)zinc(II) NLO chromophores have been carried out. A primary focus of these modifications probes the role played by porphyrin macrocycle electronic st ... Full text Cite

Utilizing Coupled-Oscillator Photophysics to Elaborate Chromophores with Exceptional Molecular Hyperpolarizabilities

Journal Article Proceedings of SPIE - The International Society for Optical Engineering · January 1, 2003 The syntheses and electrooptic properties of a family of nonlinear optical chromophores are described. Typically, these species feature an ethyne-elaborated, highly polarizable porphyrinic component, and metal polypyridyl complexes that serve as integral d ... Full text Cite

Unusual frequency dispersion effects of the nonlinear optical response in highly conjugated (polypyridyl)metal-(porphinato)zinc(II) chromophores.

Journal Article Journal of the American Chemical Society · November 2002 The syntheses and electrooptic properties of a new family of nonlinear optical chromophores are reported. These species feature an ethyne-elaborated, highly polarizable porphyrinic component and metal polypyridyl complexes that serve as integral donor and ... Full text Cite

Distance dependence of electron transfer in rigid, cofacially compressed, pi-stacked porphyrin-bridge-quinone systems.

Journal Article Journal of the American Chemical Society · July 2002 The electron-transfer (ET) dynamics of a series of unusually rigid pi-stacked porphyrin-quinone (P-Q) systems, in which sub-van der Waals interplanar distances separate juxtaposed porphyryl, aromatic bridge, and quinonyl components of these assemblies, are ... Full text Cite

Decoupling optical and potentiometric band gaps in pi-conjugated materials.

Journal Article Journal of the American Chemical Society · July 2002 Syntheses, optical spectroscopy, potentiometric studies, and electronic structural calculations are reported for two classes of conjugated (porphinato)metal oligomers that feature a meso-to-meso ethyne-bridged linkage topology. One set of these systems, bi ... Full text Cite

Extreme electronic modulation of the cofacial porphyrin structural motif.

Journal Article Journal of the American Chemical Society · April 2002 The synthesis, electrochemistry, and optical spectroscopy of an extensive series of cofacial bis[(porphinato)zinc(II)] compounds are reported. These species were synthesized using sequential palladium-catalyzed cross-coupling and cobalt-mediated [2+2+2] cy ... Full text Cite

Synthesis, excited-state dynamics, and reactivity of a directly-linked pyromellitimide-(porphinato)zinc(II) complex.

Journal Article Inorganic chemistry · February 2002 N-[5-(10,20-Diphenylporphinato)zinc(II)]-N'-(octyl)pyromellitic diimide (PZn-PI), a meso-pyromellitimide-substituted (porphinato)zinc(II) compound, has been fabricated from the reaction of (5-amino-10,20-diphenylporphinato)zinc(II) with pyromellitic dianhy ... Full text Cite

Arylethynyl-derivatized porphyrin chromophores featuring potent electron donors and acceptors for nonlinear optical applications

Journal Article American Chemical Society, Polymer Preprints, Division of Polymer Chemistry · January 1, 2002 Cite

Highly conjugated porphyrin-based chromophore systems with unusual electrooptic properties

Journal Article American Chemical Society, Polymer Preprints, Division of Polymer Chemistry · January 1, 2002 Cite

Strongly coupled porphyrin arrays featuring both pi-cofacial and linear-pi-conjugative interactions.

Journal Article Inorganic chemistry · January 2002 A combination of metal-catalyzed cross-coupling and metal-templated cycloaddition reactions have been utilized to establish multiporphyrin compounds 5-(5'-[15',15' '-bis(10' ',20' '-di[4-(3-methoxy-3-methylbutoxy)phenyl]porphinato)zinc(II)]ethyne)-6-[(5' " ... Full text Cite

High-resolution structure and conformational dynamics of rigid, cofacially aligned porphyrin-bridge-quinone systems as determined by NMR spectroscopy and ab initio simulated annealing calculations.

Journal Article Journal of the American Chemical Society · June 2001 The high-resolution solution structure and dynamics of a cofacially aligned porphyrin--phenylene--quinone compound have been determined using (1)H NMR spectroscopy and simulated annealing calculations. Members of this class of pi-stacked assemblies feature ... Full text Cite

In vitro metabolism of the COX-2 inhibitor DFU, including a novel glutathione adduct rearomatization.

Journal Article Drug metabolism and disposition: the biological fate of chemicals · May 2001 The metabolic profile of DFU [5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl)phenyl-2(5H)-furanone], a potent and selective COX-2 inhibitor, was characterized using in vitro microsomal and hepatocyte incubations. A single product, corresponding to p- ... Cite

Synthesis of Rofecoxib, (MK 0966, Vioxx® 4-(4′-Methylsulfonylphenyl)-3-phenyl-2(5H)-furanone), a selective and orally active inhibitor of cyclooxygenase-2

Journal Article Synthesis · January 1, 2001 The synthesis of Vioxx® (Rofecoxib, MK 966, 4-(4′methylsulfonylphenyl)-3-phenyl-2(5H)-furanone), a newly FDA approved inhibitor of cyclooxygenase-2, is described. ... Full text Cite

Trends in triplet excitation delocalization in highly conjugated (porphinato)zinc(II) arrays probed by EPR spectroscopy

Journal Article Synthetic Metals · January 1, 2001 The lowest photoexcited metastable triplet state of a family of highly conjugated (porphinato)zinc(II) arrays in which ethyne, butadiyne, and octatetrayne units bridge the macrocycle carbon frameworks were studied by EPR spectroscopy at low temperature in ... Full text Cite

Synthesis, characterization, and activity of metabolites derived from the cyclooxygenase-2 inhibitor rofecoxib (MK-0966, Vioxx).

Journal Article Bioorganic & medicinal chemistry letters · December 2000 Metabolites of the COX-2 inhibitor rofecoxib (MK-0966, Vioxx) were prepared by synthetic or biosynthetic methods. Metabolites include products of oxidation, glucuronidation, reduction and hydrolytic ring opening. Based on an in vitro whole blood assay, non ... Full text Cite

Syntheses and1H NMR spectroscopy of rigid, cofacially aligned, porphyrin-bridge-quinone systems in which the interplanar separations between the porphyrin, aromatic bridge, and quinone are less than the sum of their respective van der waals radii

Journal Article Journal of the American Chemical Society · September 13, 2000 Unusually rigid π-stacked porphyrin-spacer-quinone systems have been synthesized using an approach that enables extensive control over the nature of electronic interactions between donor, aromatic spacer, and acceptor. This new class of porphyrin-based str ... Full text Cite

Singlet and triplet excited states of emissive, conjugated bis(porphyrin) compounds probed by optical and EPR spectroscopic methods

Journal Article Journal of the American Chemical Society · July 26, 2000 The nature of the singlet and triplet excited states of a series of meso-to-meso ethyne-linked bis(porphyrin) compounds was probed by electronic absorption, polarized pump - probe fluorescence, electron paramagnetic resonance (EPR), electroabsorption (Star ... Full text Cite

Mechanistic studies of (porphinato)iron-catalyzed isobutane oxidation. Comparative studies of three classes of electron-deficient porphyrin catalysts.

Journal Article Inorganic chemistry · July 2000 We report herein a comprehensive study of (porphinato)iron [PFe]-catalyzed isobutane oxidation in which molecular oxygen is utilized as the sole oxidant; these catalytic reactions were carried out and monitored in both autoclave reactors and sapphire NMR t ... Full text Cite

Multilayer Langmuir-Blodgett porphyrin films for second-order non-linear optics

Journal Article American Chemical Society, Polymer Preprints, Division of Polymer Chemistry · March 1, 2000 The Langmuir-Blodgett-Kuhn (LBK) room-temperature method for making non-linear optical (NLO) polymer films is investigated. A Mach-Zender interferometer by the LBK method is made for optical modulation, demonstrating that useful devices are made from relat ... Cite

Multilayer χ(2) films from porphyrin chromophores by LBK processing

Journal Article Proceedings of SPIE - The International Society for Optical Engineering · December 1, 1999 Electrooptic films based on a new class of porphyrin chromophores with exceptionally large molecular first hyperpolarizabilities are being developed. These chromophores feature donor and acceptor groups linked to the porphyrin macrocycle at the 5- and 15-m ... Cite

Synthesis and biological evaluation of 3-heteroaryloxy-4-phenyl-2(5H)-furanones as selective COX-2 inhibitors.

Journal Article Bioorganic & medicinal chemistry letters · November 1999 A series of 3-heteroaryloxy4-phenyl-2-5H)-furanones were prepared and evaluated for their potency and selectivity as COX-2 inhibitors. This led to the identification of L-778,736 as a potent, orally active and selective inhibitor of the COX-2 enzyme. ... Full text Cite

A new structural variation on the methanesulfonylphenyl class of selective cyclooxygenase-2 inhibitors.

Journal Article Bioorganic & medicinal chemistry letters · November 1999 By inserting an oxygen link between the 3-fluorophenyl and the lactone ring of 5,5-dimethyl-3-(3fluorophenyl)-4-(4-methanesulfonylphenyl)-2 (5H)-furanone 1 (DFU), analogs with enhanced in vitro COX-2 inhibitory potency as well as in vivo potency in models ... Full text Cite

Rofecoxib [Vioxx, MK-0966; 4-(4'-methylsulfonylphenyl)-3-phenyl-2-(5H)-furanone]: a potent and orally active cyclooxygenase-2 inhibitor. Pharmacological and biochemical profiles.

Journal Article The Journal of pharmacology and experimental therapeutics · August 1999 The discoveries that cyclooxygenase (COX)-2 is an inducible form of COX involved in inflammation and that COX-1 is the major isoform responsible for the production of prostaglandins (PGs) in the gastrointestinal tract have provided a rationale for the deve ... Cite

Substituted indoles as potent and orally active 5-lipoxygenase activating protein (FLAP) inhibitors.

Journal Article Bioorganic & medicinal chemistry letters · August 1999 This paper reports on the SAR investigation of inhibitors of 5-lipoxygenase activating protein (FLAP) based on MK-0591. Emphasis was made on modifications to the nature of the link between the indole and the quinoline moieties, to the substitution pattern ... Full text Cite

The discovery of rofecoxib, [MK 966, Vioxx, 4-(4'-methylsulfonylphenyl)-3-phenyl-2(5H)-furanone], an orally active cyclooxygenase-2-inhibitor.

Journal Article Bioorganic & medicinal chemistry letters · July 1999 The development of a COX-2 inhibitor rofecoxib (MK 966, Vioxx) is described. It is essentially equipotent to indomethacin both in vitro and in vivo but without the ulcerogenic side effect due to COX-1 inhibition. ... Full text Cite

Syntheses, NMR and EPR spectroscopy, electrochemical properties, and structural studies of [5,10,15,20- tetrakis(perfluoroalkyl)porphinato]iron(II) and -iron(III) complexes

Journal Article Journal of the American Chemical Society · June 9, 1999 Syntheses, structural studies, electrochemistry, and spectroscopy of a number of [5,10,15,20-tetrakis(heptafluoropropyl)porphinato]iron derivatives are presented. The X-ray crystal structure of 5,10,15,20- tetrakis(heptafluoropropyl)porphinato]iron(II)·(py ... Full text Cite

Suzuki porphyrins: New synthons for the fabrication of porphyrin- containing supramolecular assemblies [6]

Journal Article Journal of the American Chemical Society · December 9, 1998 Full text Cite

Ultrafast dynamics of highly conjugated porphyrin arrays

Journal Article Journal of the American Chemical Society · November 11, 1998 The photophysical properties of a series of ethynyl-bridged (porphinato)zinc(II) oligomers have been investigated over the femtosecond and picosecond time scales using ultrafast magic angle and polarized pump- probe spectroscopy. Bis[(2,2',-5,10,15,20- tet ... Full text Cite

Synthesis of porphyrin-spacer-quinone compounds via metal-mediated cross-coupling: New systems for probing the relative magnitudes of axial and equatorial electronic coupling at the porphyrin macrocycle in thermal and photoactivated electron transfer reactions

Journal Article Inorganica Chimica Acta · July 1, 1998 Two classes of (porphinato)zinc(II)-spacer-quinone electron transfer compounds were fabricated through metal-mediated cross-coupling reactions using appropriately derivatized porphyrin, dimethoxybenzene and phenylene spacer moieties. The syntheses of these ... Full text Cite

Electronic stark effect studies of a porphyrin-based push-pull chromophore displaying a large first hyperpolarizability: State-specific contributions to β

Journal Article Journal of the American Chemical Society · March 25, 1998 Electroabsorption or Stark effect spectroscopy has been applied to a pair of porphyrin-based chromophores with the aim of deriving a detailed understanding of the origin of the remarkable first hyperpolarizability, β, of one of the chromophores: [5-[[4'-(d ... Full text Cite

Synthesis, Transient Absorption, and Transient Resonance Raman Spectroscopy of Novel Electron Donor-Acceptor Complexes:  [5,15-Bis[(4'-nitrophenyl)ethynyl]-10,20- diphenylporphinato]copper(II) and [5-[[4'-(Dimethylamino)phenyl]ethynyl]-15-[(4''-nitrophenyl)ethynyl]-10,20-diphenylporphinato]copper(II).

Journal Article Journal of the American Chemical Society · December 1997 We report the synthesis, transient absorption, FT Raman, resonance Raman, time-resolved resonance Raman, and transient resonance Raman spectra of pseudo-D 2h symmetric [5,15-bis[(4'-nitrophenyl)ethynyl]-10,20-diphenylporphinato]copper ... Full text Cite

A selective inhibitor of cyclooxygenase-2 reverses endotoxin-induced pyretic responses in non-human primates.

Journal Article European journal of pharmacology · May 1997 The anti-pyretic effect of a selective cyclooxygenase-2 inhibitor, DFU (5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulfonyl)phenyl-2(5H)-furano ne), was examined in conscious, un-restrained squirrel monkeys (Saimiri sciureus) using a radio telemetric syste ... Full text Cite

Biochemical and pharmacological profile of a tetrasubstituted furanone as a highly selective COX-2 inhibitor.

Journal Article British journal of pharmacology · May 1997 1. DFU (5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl)phenyl-2(5H)-furan one) was identified as a novel orally active and highly selective cyclo-oxygenase-2 (COX-2) inhibitor. 2. In CHO cells stably transfected with human COX isozymes, DFU inhibited ... Full text Cite

Synthesis and biological evaluation of 5,6-diarylimidazo[2.1-b]thiazole as selective COX-2 inhibitors

Journal Article Bioorganic and Medicinal Chemistry Letters · January 7, 1997 A series of 5,6-diarylimidazo[2.1-b]thiazole compounds were prepared and their inhibitory potencies against COX-2 and Cox-1 enzymes were measured. This led to the identification of L-766,112 as a potent, orally active and selective inhibitor of the COX-2 e ... Full text Cite

A new series of selective COX-2 inhibitors: 5,6-diarylthiazolo[3,2-b][1,2,4]triazoles

Journal Article Bioorganic and Medicinal Chemistry Letters · January 7, 1997 A series of 5,6-diarylthiazolo[3,2-b][1,2,4]triazoles was prepared for evaluation of potency and selectivity against human COX-1 and COX-2 enzymes. This lead to the discovery of L-768,277, a potent and selective COX-2 inhibitor that also demonstrated good ... Full text Cite

Thermally stable, highly nonlinear porphyrin-based chromophores in poled host-guest thin films

Journal Article Journal of Engineering and Applied Science · December 1, 1996 A new class of chromophores has been fabricated that features both electron-releasing and electron-withdrawing groups fused via an intervening ethynyl moiety to the carbon framework of a (porphinato)metal complex. These species possess a number of unusual ... Cite

Exceptional electronic modulation of porphyrins through meso-arylethynyl groups. Electronic spectroscopy, electronic structure, and electrochemistry of [5,15-bis](aryl)ethynyl]-10,20-diphenylporphinato]zinc(II) complexes

Journal Article Journal of the American Chemical Society · November 27, 1996 A new class of porphyrins in which intervening ethynyl moieties connect aryl groups to the porphyrin 5 and 15-positions is described. The synthesis and optical spectroscopy of five new compounds are reported: [5,15-bis[(4'-dimethylaminophenyl)ethynyl]-10,2 ... Full text Cite

Synthesis, structure, electronic spectroscopy, photophysics, electrochemistry, and X-ray photoelectron spectroscopy of highly-electron-deficient [5,10,15,20-tetrakis(perfluoroalkyl)porphinato]zinc(II) complexes and their free base derivatives

Journal Article Journal of the American Chemical Society · September 4, 1996 The synthesis, optical spectroscopy, photophysical properties, electrochemistry, and X-ray photoelectron spectroscopy of a series of [5,10,15,20-tetrakis(perfluoroalkyl)porphinato]zinc(II) complexes and their free base analogs are reported. The title compo ... Full text Cite

Synthesis of (porphinato)zinc(II)-spacer-(porphinato)iron(III) chloride complexes: A modular approach to fixed-distance electron-transfer model compounds through the efficacy of metal-mediated cross-coupling

Journal Article Inorganica Chimica Acta · February 15, 1996 The syntheses of (porphinato)zinc(II)-spacer-(porphinato)iron(III) chloride complexes were effected by the agency of Pd-catalyzed cross-coupling of two equivalents of [5-bromo-10,20-diphenyl-15-(4′-methoxyphenyl)porphinato]zinc with a symmetric bis(trimeth ... Full text Cite

Acetylenyl-linked, porphyrin-bridged, donor-acceptor molecules: A theoretical analysis of the molecular first hyperpolarizability in highly conjugated push-pull chromophore structures

Journal Article Journal of the American Chemical Society · February 14, 1996 We described the theoretical basis for the exceptionally large molecular first hyperpolarizabilities inherent to (5,15-diethynyl)porphinato)metal-bridged donor-acceptor (D-A) molecules. β values relevant for hyper-Rayleigh experiments are calculated at 1.0 ... Full text Cite

Push-pull arylethynyl porphyrins: New chromophores that exhibited large molecular first-order hyperpolarizabilities

Journal Article Journal of the American Chemical Society · January 1, 1996 A new class of chromophores has been fabricated that features both electron-releasing and electron-withdrawing groups fused via and intervening ethynyl moiety to the carbon framework of a (porphinato)metal complex. These species possess large molecular fir ... Full text Cite

Thiopyranol[2,3,4-c,d]indoles as inhibitors of 5-lipoxygenase, 5-lipoxygenase-activating protein, and leukotriene C4 synthase.

Journal Article Journal of medicinal chemistry · October 1995 The attachment of an arylacetic or benzoic acid moiety to the thiopyrano[2,3,4-c,d]indole nucleus results in compounds which are highly potent and selective 5-lipoxygenase (5-LO) inhibitors. These compounds are structurally simpler than previous compounds ... Full text Cite

Direct evaluation of electronic coupling mediated by hydrogen bonds: implications for biological electron transfer.

Journal Article Science (New York, N.Y.) · September 1995 Three supramolecular bischromophoric systems featuring zinc(II) and iron(III) porphyrins have been synthesized to evaluate the relative magnitudes of electronic coupling provided by hydrogen, sigma, and pi bonds. Laser flash excitation generates the highly ... Full text Cite

The Role of Porphyrin‐to‐Porphyrin Linkage Topology in the Extensive Modulation of the Absorptive and Emissive Properties of a Series of Ethynyl‐ and Butadiynyl‐Bridged Bis‐ and Tris(porphinato)zinc Chromophores

Journal Article Chemistry – A European Journal · January 1, 1995 A new method for the regulation of the photophysical properties of highly conjugated porphyrin arrays is described. The absorptive and emissive signatures of such supramolecular structures can be modulated to an impressive degree by regulation of: i) the e ... Full text Cite

Porphyrin—Quinone Electron Transfer Revisited. The Role of Excited-State Degeneracy in Ultrafast Charge Transfer Reactions

Journal Article Journal of the American Chemical Society · January 1, 1995 Ultrafast time-resolved anisotropy experiments in which electronically excited [5-(1‘,4’-benzoquinonyl)- 10,15,20-triphenylporphinato]magnesium (MgPQ) was probed with polarization both parallel and perpendicular to the pump pulse have been carried out in a ... Full text Cite

EPR Spectroscopy and Photophysics of the Lowest Photoactivated Triplet State of a Series of Highly Conjugated (Porphinato)Zn Arrays

Journal Article Journal of the American Chemical Society · January 1, 1995 The lowest photoexcited metastable triplet state of a family of highly conjugated (porphinato)zinc(II) arrays in which ethyne or butadiyne units bridge the macrocycle carbon frameworks, along with their ethyne- and butadiyne-elaborated monomeric porphyrini ... Full text Cite

Facile Synthesis of meso-Tetrakis(perfluoroalkyl)porphyrins: Spectroscopic Properties and X-ray Crystal Structure of Highly Electron-Deficient 5,10,15,20-Tetrakis(heptafluoropropyl)porphyrin

Journal Article Journal of Organic Chemistry · November 1, 1994 The synthesis, structure, optical spectrum, and electrochemistry of 5,10,15,20-tetrakis(perfluoropropyl)porphyrin, 1, are reported. The high yield preparative method, starting from (hydroxymethyl)pyrrole precursors such as 2,2,3,3,4,4,4-heptafluoro-1-(2-py ... Full text Cite

Highly conjugated, acetylenyl bridged porphyrins: new models for light-harvesting antenna systems.

Journal Article Science (New York, N.Y.) · May 1994 A new class of porphyrin-based chromophore systems has been prepared from ethyne-elaborated porphyrin synthons through the use of metal-mediated cross-coupling methodologies. These systems feature porphyrin chromophores wired together through single ethyny ... Full text Cite

Thiopyrano[2,3,4-cd]indoles as 5-lipoxygenase inhibitors: synthesis, biological profile, and resolution of 2-[2-[1-(4-chlorobenzyl)-4-methyl-6-[(5-phenylpyridin-2-yl)methoxy]-4,5 -dihydro-1H-thiopyrano[2,3,4-cd]indol-2-yl]ethoxy]butanoic acid.

Journal Article Journal of medicinal chemistry · April 1994 Leukotriene biosynthesis inhibitors have potential as new therapies for asthma and inflammatory diseases. The recently disclosed thiopyrano[2,3,4-cd]indole class of 5-lipoxygenase (5-LO) inhibitors has been investigated with particular emphasis on the side ... Full text Cite

Substituted thiopyrano[2,3,4-c,d]indoles as potent, selective, and orally active inhibitors of 5-lipoxygenase. Synthesis and biological evaluation of L-691,816.

Journal Article Journal of medicinal chemistry · September 1993 Thiopyrano[2,3,4-c,d]indoles are a new class of 5-lipoxygenase (5-LO) inhibitors. SAR studies have demonstrated that the thiopyran ring, the 5-phenylpyridine substituent, and an acidic functional group on a four-carbon C-2 side chain are all required for o ... Full text Cite

Direct measurement of electronic dephasing using anisotropy

Journal Article Chemical Physics Letters · May 7, 1993 In a recent theoretical treatment of coherence effects in the anisotropy of optical experiments, it was predicted that the decay of the anisotropy that exists for molecules with degenerate states prior to the onset of electronic dephasing could be utilized ... Full text Cite

Justicidin E: A new leukotriene biosynthesis inhibitor.

Journal Article Bioorganic and Medicinal Chemistry Letters · January 1, 1993 Justicidin E, an arylnaphthalene lignan, has been identified as a potent inhibitor of leukotriene biosynthesis by human leukocytes (IC50 = 70 nM) and a non-redox inhibitor of 5-lipoxygenase activity. © 1993. ... Full text Cite

Vibrational coherence in charge transfer

Journal Article Springer Series in Chemical Physics · January 1, 1993 We present the first ultrafast studies on free-base triphenyl-porphyrin-quinone(5-(1',-4'-benzoquinonyl)-10,15, 20-triphenylporphyrin or PQ).There are strong indications that coherence of nuclear or electronic origin plays a role in the ET transfer reactio ... Cite

Facile Elaboration of Porphyrins via Metal-Mediated Cross-Coupling

Journal Article Journal of Organic Chemistry · January 1, 1993 Metal-mediated cross-coupling methodologies have been successfully employed to porphyrinic systems, providing a powerful, versatile, and general synthetic approach for the fabrication of elaborated porphyrin structures. A large number of coupling reactions ... Full text Cite

Development of a novel series of styrylquinoline compounds as high-affinity leukotriene D4 receptor antagonists: synthetic and structure-activity studies leading to the discovery of (+-)-3-[[[3-[2-(7-chloro-2-quinolinyl)-(E)-ethenyl]phenyl][[3- (dimethylamino)-3-oxopropyl]thio]methyl]thio]propionic acid.

Journal Article Journal of medicinal chemistry · October 1992 Based on LTD4 receptor antagonist activity of 3-(2-quinolinyl-(E)-ethenyl)pyridine (2) found in broad screening, structure-activity studies were carried out which led to the identification of 3-[[[3-[2-(7-chloro-2-quinolinyl)-(E)-ethenyl]phenyl][[3- (dimet ... Full text Cite

Formation of a novel thiopyranoindole ring system

Journal Article Tetrahedron Letters · August 11, 1992 The novel thiopyran[2,3,4-c,d]indole ring system (e.g.3) has been prepared from a substituted indole by intramolecular cyclisation of a t-BuS group onto an allyl substituent. The reaction occurs in high yield under the influence of protic acids, Lewis acid ... Full text Cite

5-Lipoxygenase-activating protein is the target of a quinoline class of leukotriene synthesis inhibitors.

Journal Article Molecular pharmacology · July 1991 An indole class of leukotriene synthesis inhibitors, exemplified by MK-886, which does not directly inhibit 5-lipoxygenase, has been shown to bind to an 18-kDa leukocyte membrane protein and to inhibit 5-lipoxygenase membrane translocation. It was demonstr ... Cite

A new class of leukotriene biosynthesis inhibitors: The development of ((4-(4-chlorophenyl)-1-(4-(2-quinolinylmethoxy)phenyl)butyl)thio)acetic acid, L-674,636

Journal Article Bioorganic and Medicinal Chemistry Letters · January 1, 1991 A new, potent and orally active leukotriene synthesis inhibitor has been developed. © 1991. ... Full text Cite

Stereospecific synthesis, assignment of absolute configuration, and biological activity of the enantiomers of 3-[[[3-[2-(7-chloroquinolin-2-yl)-(E)-ethenyl]phenyl] [[3-(dimethylamino)-3-oxopropyl]thio]methyl]thio]propionic acid, a potent and specific leukotriene D4 receptor antagonist.

Journal Article Journal of medicinal chemistry · October 1990 The enantiomers of the leukotriene D4 antagonist 3-[[[3-[2-(7-chloroquinolin-2-yl)-(E)-ethenyl]phenyl] [[3-(dimethylamino)-3-oxopropyl]thio]methyl]thio]propionic acid (L-660,711)(MK-571) have been prepared, their absolute stereochemistry has been assigned ... Full text Cite

Electrochemical studies of an oxidatively induced ring slippage in 17-electron (η3-indenyl)(η5-indenyl)V(CO)2

Journal Article Journal of Organometallic Chemistry · February 20, 1990 Oxidation of (η5-arene)2V (arene = indenyl, C5H5, C5Me5) with [(C5H5)2Fe][PF6] under a carbon monoxide atmosphere provides a convenient route to [(η5-arene)2V(CO)2]+ complexes. The cyclic voltammogram of the indenyl compound shows two reversible one-electr ... Full text Cite

Asymmetric dithioacetals III: The preparation of the enantiomers of 3-((((3-(2-(7-chloroquinolin-2-YL)-(E)-ethenyl)phenyl)-3-dimethylamino-3-oxopropylthio)methyl)thio)propionic acid (l-660,711) (mk-571), an antagonist of leukotriene D4

Journal Article Heterocycles · January 1, 1989 The application of a novel method for the preparation of chiral dithioacetals to the synthesis of the enantiomers of L-660,711, an antagonist of leukotriene D4, is described. Reaction of 3-(t-butyld1phenylsilyloxymethyl)benzaldehyde or isophthalaldehyde wi ... Full text Cite

Spectroscopic, Structural, Electrochemical, and Kinetic Studies of Ligand Substitution in the 33e Dinuclear Radical Fe2(CO)7(μ-PPh2) and the 34e Analogues [Fe2(CO)7(μ-PPh2)]_and FeCo(CO)7(μ-PPh2)

Journal Article Journal of the American Chemical Society · January 1, 1988 The 33e dinuclear radical Fe2(CO)7(μ-PPh2) undergoes rapid CO ligand substitution with a variety of tertiary phosphorus ligands, L, to give mono- and disubstituted 33e products, which were characterized by elemental analysis and by IR and ESR spectroscopy. ... Full text Cite

A novel and efficient method for the preparation of asymmetric dithioacetals

Journal Article Tetrahedron Letters · January 1, 1988 Aldehydes and ketones react with one equivalent each of thiols and thiolacetic acid under acid catalysis to yield almost exclusively the mixed alkylthio-(or arylthio-) acylthioacetals. Reaction of the mixed thioacetal with a nucleophile (such as NaOMe) lib ... Full text Cite

Asymmetric dithioacetals II: A novel and versatile method for the preparation of chiral dithioacetals

Journal Article Tetrahedron Letters · January 1, 1988 Reaction of aldehydes with one equivalent each of a thiol and a chiral thiolacid such as (R)-(-)-α-methoxyphenylthiolacetic acid in the presence of an acidic catalyst such as ZnI2 or p-toluenesulfonic acid yields diastereomeric mixed thioacetals in good yi ... Full text Cite

Spectroscopic, structural, electrochemical, and kinetic studies of ligand substitution in the 33e dinuclear radical Fe2(CO)7(μ-PPh2) and the 34e analogues [Fe2(CO)7(μ-PPh2)]- and FeCo(CO)7(μ-PPh2)

Journal Article Journal of the American Chemical Society · 1988 The 33e dinuclear radical Fe2(CO)7(μ-PPh2) undergoes rapid CO ligand substitution with a variety of tertiary phosphorus ligands, L, to give mono- and disubstituted 33e products, which were characterized by elemental analysis and by IR and ESR spectroscopy. ... Cite

Theoretical Study of Bimolecular Nucleophilic Substitution at Four-, Five-, and Six-Coordinate Metal Carbonyl Radicals

Journal Article Journal of the American Chemical Society · January 1, 1988 Walsh diagrams, contour maps, and the atomic character and energies of the frontier molecular orbitals derived from SCF-Xα-DV calculations have been employed to deduce the most favorable mode of nucleophilic attack at homoleptic metal carbonyl radicals con ... Full text Cite

Selective loss of CO in the photochemistry of MnRe(CO)10: a study using matrix isolation and time-resolved infrared spectroscopy

Journal Article Journal of Organometallic Chemistry · September 15, 1987 Photolysis of MnRe(CO)10, in argon matrices or room temperature solution, causes dissociation of CO and the formation of a singly bridged intermediate, (CO)4Mn(μ-CO)Re(CO)4. The reaction has been studied using samples specifically enriched with 13CO on the ... Full text Cite

First Synthesis of Sulfoxides and Sulfones in the 3H-Phenothiazin-3-one and 5H-Benzo[a ]phenothiazin-5-one Ring Systems. Addition Reactions with Nucleophiles

Journal Article Journal of Organic Chemistry · September 1, 1987 We report the first synthesis of sulfoxides and sulfones in the 3H-phenothiazin-3-one and 5H-benzo[a]-phenothiazin-5-one ring systems. The pronounced reactivity of the parent compounds 2a, 2b, 4a, and 4b does not allow their isolation, but they can be conv ... Full text Cite

Mechanism of Oxidatively Induced Migratory Insertion of Carbon Monoxide: Evidence for a 19-Electron Intermediate

Journal Article Journal of the American Chemical Society · August 1, 1987 The mechanism of oxidatively induced CO insertion for CpFe(CO)(PPh3)CH3has been probed by transient electrochemical techniques. the data presented herein suggest that the alkyl-to-acyl migration at 17-electron CpFe(CO)-(PPh3)CH3+proceeds by a mechanism con ... Full text Cite

Regiocontrolled Opening of Cyclic Ethers Using Dimethylboron Bromide

Journal Article Journal of Organic Chemistry · May 1, 1987 The cleavage of various cyclic ethers (3- to 7-membered rings) was achieved under very mild conditions using dimethylboron bromide to afford the corresponding bromo alcohols. In particular, 2-substituted tetrahydrofurans were regioselectively cleaved by a ... Full text Cite

Tricarbonylbis(phosphine)iron(I) Cation Radicals. A Spectroscopic and Theoretical Study

Journal Article Journal of the American Chemical Society · January 1, 1986 : Comparison of the IR spectra of Fe(CO)3(PPh3)2 and the 17-electron complex [Fe(CO)3(PPh3)2] [PF6], each enriched 50% and 93% with 13CO, shows that the 17-electron d7 radical retains the trigonal-bipyramidal structure (D3hcoordination symmetry) of the par ... Full text Cite

Kinetics of Disproportionation of Tricarbonylbis(phosphine)iron(I) Cation Radicals Probed by Double Potential Step Chronocoulometry

Journal Article Journal of the American Chemical Society · January 1, 1986 Rates of substitution of carbon monoxide in a series of iron(I) radical complexes were measured by using double potential step chronocoulometry, a transient electrochemical technique. Carbon monoxide substitution in Fe(CO)3L2+ (L = a phosphine) radicals pr ... Full text Cite

Synthesis of Amines through Nucieophilic Addition on Nitrogen

Journal Article Journal of the American Chemical Society · September 1, 1984 Full text Cite

Stereocontrolled Synthesis of the Spiro Ketal Unit of Avermectin B1a Aglycon

Journal Article Journal of Organic Chemistry · January 1, 1983 A stereocontrolled total synthesis of the 1,7- dioxaspiro[5.5]undecene subunit of the avermectin Bla aglycon is presented based on the “chiron” approach which utilizes optically active starting materials. © 1983, American Chemical Society. All rights reser ... Full text Cite

Synthesis of 4-amino-4(S)-dihydrospectinomycin.

Journal Article The Journal of antibiotics · March 1981 Full text Cite