6alfa compounds of chlorine, Bromine or iodine (R) - 1 (R) (6beta hydroxy etilpenicilina, useful as Intermediates for the sistensis Carbapenem Antibiotics and penem and Procedure to prepare them.

摘要

A novel stereocontrolled process is disclosed for converting 6-aminopenicillanic acid to an optically active azetidinone of the formula IMAGE wherein R'' is a hydroxy-protecting group by use of a 6,6-dihaloanhydropenicillin or 6,6-bis(phenylselenyl)anhydropenicillin intermediate.