| 摘要 |
<p>Stable crystals of diphenylmethyl 2-methyl-2-triazolyl-methylpenam-3-carboxylate, which cause substantially no decomposition or deterioration even after allowing to stand at room temperature for one year. The crystals are produced by concentrating a solution of diphenylmethyl 2-methyl-2-triazolylmethylpenam-3-carboxylate of formula (2), diluting the resulting concentrate with an acetic ester, and mixing the obtained dilution with hexane or a hexane/acetic ester mixture to crystallize diphenylmethyl 2-methyl-2-triazolylmethyl-penam-3-carboxylate wherein Ph is phenyl.</p> |
