| abstract |
To prepare, for example, 4'-nitrobenzyl-7-phenoxyacetamide-3-hydroxy-3-cephem-4-carboxylate acetic acid solvate, a solution of 4'-nitrobenzyl-7-phenoxyacetamido-3-hydroxy-3-cephem-4 After completion of the reaction, propylene carbonate is added to increase the solubility of the 3-hydroxysulfide. After completion of the reaction, washing and concentration of acetic acid is added, whereupon the desired compound crystallized. |