Kleinhospitine E and Cycloartane Triterpenoids from Kleinhovia hospita.

Journal Article (Journal Article)

A novel cycloartane triterpenoid alkaloid, kleinhospitine E (1), six new cycloartane triterpenoids (2-7), three known cycloartane triterpenoids (8-10), and taraxerone (11) were isolated from a methanol extract of Kleinhovia hospita. Their structures were elucidated by 1D- and 2D-NMR spectroscopy as well as HRMS analysis. The absolute configurations of all isolated compounds were determined from their ECD spectra by comparison with theoretical values. Kleinhospitine E (1) is the first cycloartane alkaloid possessing an unusual γ-lactam with an oxopropylidene side chain. Compounds 2, 3, and 6 were assigned as cycloartane triterpenoids with a 9α,10α-cyclopropyl ring, which is found rarely among naturally occurring compounds, while 4 and 5 were established as isomers of compound 3 containing a 21,23-diacetal side chain. Biological evaluation revealed that compounds 4 and 9 exhibited more potent antiproliferative activities against a multidrug-resistant tumor cell line compared with its parent chemosensitive cell line. Furthermore, compound 6 exhibited submicromolar anti-HIV activity.

Full Text

Duke Authors

Cited Authors

  • Rahim, A; Saito, Y; Miyake, K; Goto, M; Chen, C-H; Alam, G; Morris-Natschke, S; Lee, K-H; Nakagawa-Goto, K

Published Date

  • July 27, 2018

Published In

Volume / Issue

  • 81 / 7

Start / End Page

  • 1619 - 1627

PubMed ID

  • 30010341

Pubmed Central ID

  • PMC6464124

Electronic International Standard Serial Number (EISSN)

  • 1520-6025

Digital Object Identifier (DOI)

  • 10.1021/acs.jnatprod.8b00211


  • eng

Conference Location

  • United States