Process for the preparation of perindopril, its analgous compounds and salts therof using 2,5 dioxo-oxazolidine intermediate compounds

摘要

A process for the preparation of a compound of formula (IV), or an ester or a salt thereof comprising 1) reacting a compound of formula (I), (wherein Ra represents C1-4 alkyl, Rb represents C1-4 alkyl and Rc represents C1-6 alkyl) with a compound of formula X2C=0 (wherein each X independently represents a leaving group) to give a compound of formula (II), (wherein Ra, Rb and Rc are as hereinbefore defined); and 2) reacting said compound of formula (II) with a compound of formula (III) (wherein Rd represents hydrogen or a protecting group).