Resolution of trans-2-(alkoxycarbonylethyl)-lactams useful in the synthesis of 1-(4-fluoro-phenyl)-3(R)-[(S)-hydroxy-3-(4-fluorophenyl)-propyl]-4(S)-(4-hydroxyphenyl)-2-azetidinone

摘要

A process for the microbiological or enzymatic hydrolytic resolution of racemic trans-2-(alkoxycarbonylethyl) lactams of the formula I: wherein R is C1-C7 alkyl, 2,2,2-trifluoroethyl or methoxyethoxyethyl and R1 is hydrogen or a protecting group is disclosed, whereby an optically enriched compound of the formula Ib or IIa: is obtained.