Optically-active dihydropyridines via lipase-catalyzed enantioselective hydrolysis

Several prochiral esters of 1,4-dihydropyridines were enantioselectively hydrolyzed by Pseudomonas lipases (AK, P-30, and K-10) and Candida cylindracea lipase (OF-360). The stereochemical preferences of the lipases P-30 and K-10 were found to be always 4-Pro R and that of OF-360 to be 4-Pro S. In contrast, the prochiral preference of the lipase AK varied depending on the substitution on the dihydropyridine ring. The N-methoxymethyl derivatives afforded the 4S isomers (95% ee) whereas the N-unsubstituted compounds yielded the 4R isomers (50–70% ee).