| 摘要 |
<p>Intermediates and a stepwise process for the conversion of D-methionine or certain of its derivatives to optically active compounds of the formula <CHEM> wherein R is (C1-C3)alkyl, phenyl or tolyl. The latter compounds are in turn useful as an intermediate in the preparation of penem antibiotic 5R,6S-6-(1R-hydroxyethyl)-2-(1R-oxo-3S-thiola nylthio)-2-penem-3-carboxylic acid and corresponding pharmaceutically acceptable salts and esters.</p> |
