摘要 |
Process and intermediates for the conversion of 3R,4R-4-acetoxy-3-[1R-1-(silyloxy)ethyl]-2-azetidinones to antibacterial 5R,6S-6-(1R-1-hydroxyethyl)-2-(1-oxo-3-thiolanylthio)-2-penem-3-carbox ylic acids, and the pharmaceutically-acceptable salts and pivaloyloxymethyl esters thereof. |