175474-15-4Relevant articles and documents
A Practical and Efficient Synthesis of the Selective Neuronal Acetylcholine-Gated Ion Channel Agonist (S)-(-)-5-Ethynyl-3-(1-methyl-2-pyrrolidinyl)pyridine Maleate (SIB-1508Y)
Bleicher, Leo S.,Cosford, Nicholas D. P.,Herbaut, Audrey,Stuart McCallum,McDonald, Ian A.
, p. 1109 - 1118 (2007/10/03)
An efficient, high-yielding synthetic procedure for the preparation of the novel neuronal acetylcholinegated ion channel agonist (S)-(-)-5-ethynyl-3-(1-methyl-2-pyrrolidinyl)pyridine maleate [(S)-2, SIB-1508Y] is described. The key steps in the process include the lithium bis(trimethylsilyl)amide-mediated acylation of N-vinylpyrrolidinone with ethyl 5-bromonicotinate, a high-yielding sodium borohydride reduction of imine 5, and a new heteroaryl-alkyne cross-coupling protocol for the introduction of the ethyne moiety in (S)-2. The preparation of enantiomerically pure (S)-2 was accomplished via a combination of enantioselective reduction of imine 5 and crystallization of enantiomerically enriched 5-bromo-3-(1-methyl-2-pyrrolidinyl)pyridine (7) as the dibenzoyl-L-tartaric acid salt.