摘要 |
<p>7 beta -Acylamino-3-trifluoromethylsulfonyloxy-1-carba-3-cephem-4-carboxylic acid antibiotic compounds, esters and salts thereof, and the corresponding 7-amino and protected 7-amino 1-carbacephalosporins are provided. The 3-trifluoromethylsulfonyloxy-substituted 1-carbacephalosporins also are useful in a process for preparing 3-halo-1-carbacephalosporins which comprises reacting a 3-triflate ester with a lithium halide in an aprotic polar solvent.</p> |