| abstract |
The present invention describes methods and materials for preparing pharmaceutically acceptable salts thereof, including quinapril, quinapril hydrochloride. The process of the invention comprises (2S, 4S) -2- (4--methyl-2,5-dioxo-oxazolidin-3-yl) -4-phenyl-butyric acid ethyl ester (3S) -1,2 Reacting 3,4-tetrahydro-isoquinoline-3-carboxylic acid tert-butyl ester to obtain quinaprill tert-butyl ester, which is then reacted with an acid to obtain quinapril or acid addition salts of quinapril. do. |