Patent ID: 6255463
Filing Date: 2001-07-03
Classification: C07H,Y02P

Abstract:
A process for preparing a compound of the formula (I): ##STR5##wherein R.sup.1 is H or a hydroxyimino-protecting group; R.sup.2 is H, C.sub.1-4 alkyl or C.sub.1-4 alkoxy; R.sup.3 is C.sub.1-8 alkyl, C.sub.2-8 alkenyl or C.sub.3-8 cycloalkyl; and R.sup.4 is H, halo, C.sub.1-4 alkyl or C.sub.1-4 alkoxy, which process comprises the steps of:(a) reacting a compound of formula (II): ##STR6##with an oxidizing agent to form a 5-oxo compound;(b) allowing the 5-oxo compound to react with a compound of formula R.sup.1 --O--NH.sub.2 wherein R.sup.1 is H or a hydroxyimino-protecting group, to form a 5-imino compound;(c) reacting the 5-imino compound with a thionocarbonizing agent to form a 4"", 23-bisthionocarbonyl ester;(d) reacting the 4"", 23-bisthionocarbonyl ester with a deoxygenation agent to form a 4"", 23-dideoxy compound; and(e) reacting the 4"", 23-dideoxy compound with an acid to form a compound of the formula (I).