Patent ID: 6410756
Filing Date: 2002-06-25
Classification: C07D

Abstract:
A process for the preparation of a compound of formula III: where R3 is selected from the group consisting of n-propyl, isopropyl and n-butyl, or a pharmaceutically acceptable salt thereof; which comprises:(a) deprotecting a compound of formula IV: â€ƒwherein R3 is selected from the group consisting of n-propyl, isopropyl and n-butyl; or: (b) treating the compound of formula V: â€ƒwherein R4 is â€”SiEt3; with organic acid, followed by an acylation step using bicarbonate and an acyl chloride in a one pot reaction, or (c) deprotecting a compound of formula VI: â€ƒwherein R3 is selected from the group consisting of n-propyl, isopropyl and n-butyl.