Patent ID: 6897311
Filing Date: 2005-05-24
Classification: C07D,Y02P

Abstract:
1. A process for the preparation of the compounds of general formula (I) in which the groups R are both hydrogen, or one is hydrogen and the other is a straight or branched C 1 -C 4 alkyl group, optionally substituted with one or more —OPg-protected hydroxy groups, in which Pg is a hydroxy-protecting group, which process comprises: step a) reacting a compound of general formula (IV), in which, both of the groups X 1 are hydrogen or both are CH 2 and both of the groups X 2 are hydrogen or both are CH 2 , provided that when the groups X 1 are hydrogen, the groups X 2 form a —CH 2 CH 2 — and when the groups X 1 are a —CH 2 CH 2 — group, then the groups X 2 are hydrogen, with a compound of general formula (VI) in which A is a group of formula —COR 1 or —CHRR 2 wherein R has the meaning defined above, R 1 is halogen or a C 1 -C 4 alkoxy group and R 2 is a leaving group such as halogen or sulfonyloxy, in at least unitary molar ratio, at a temperature above 50° C.; step b) reducing the compounds obtained from step a), having general formula (III) in which one of Y 1 or Y 2 is —CH 2 —CH 2 — and the other is —CO—CO— or a group of formula —COCHR, wherein R has the meaning defined above, in the presence of an amido-reducing agent.