| 摘要 |
Crystalline p-nitrobenzyl 7 beta -phenoxyacetylamino-3-hydroxy-1-carba(dethia)-3-cephem-4-carboxylate and the crystalline mono-acetic acid solvate thereof are provided by mixing a carboxylic acid or a sulfonic acid with a solution of the 3-hydroxy ester in DMF or DMAC. Acetic acid provides the crystalline acetic acid solvate while other acids provide crystalline non-solvated 3-hydroxy ester. The crystalline forms are useful purified intermediates to antibiotics. |
