Radiosynthesis of 5-(2-(4-pyridinyl)vinyl)-6-chloro-3-(1-[(11)C]methyl-2-(S)-pyrrolidinylmethoxy)pyridine, a high affinity ligand for studying nicotinic acetylcholine receptors by positron emission tomography.

5-(2-(4-pyridinyl)vinyl)-6-chloro-3-(1-methyl-2-(S)-pyrrolidinylmethoxy)pyridine (1b) exhibited high affinity for nicotinic acetylcholine receptors in the in vitro competition binding assays, with a K(d) value in the low picomolar range, performed at room temperature and at physiological temperature. An efficient radiochemical synthesis of 5-(2-(4-pyridinyl)vinyl)-6-chloro-3-(1-[(11)C]methyl-2-(S)-pyrrolidinylmethoxy)pyridine (1c), a potential tracer for the study of nAChR by positron emission tomography, has been developed.