A novel process for preparing enantiomerically-pure 3-methyl-5-(1-(C.sub.1 -C.sub.3 -alkyl)-2-pyrrolidinyl)isoxazole in high yield, wherein a protected pyrrolidine or 2-oxo-pyrrolidine starting material is reacted with a suitable organic anion and a resulting beta-keto oxime intermediate is cyclized and dehydrated, as well as intermediates useful in the preparation thereof.
A Short, Efficient Synthesis of the Novel Cholinergic Channel Activator, ABT 418, from L-Proline
作者:Richard L. Elliott、Hana Kopecka、Nan-Horng Lin、Yun He、David S. Garvey
DOI:10.1055/s-1995-4014
日期:1995.7
A short and efficient synthesis of the novel cholinergic channel activator ABT 418, (S)-3-methyl-5-(1-methyl-2-pyrrolidinyl)isoxazole, has been developed. The four-step route from L-proline afforded the target compound in ca. 35% overall yield in very high chemical and enantiomeric purity. This route has afforded multigram quantities of the clinical candidate and should be amenable to kilogram-scale reactions.