反应详情

A powder (0.2 g) of 7-[2-ethoxyimino-2-(5-amino-1,2,4-thiadiazol-3-yl)acetamido]-3-(1-pyridiniomethyl)-3-cephem-4-carboxylate (syn isomer) was dissolved in water (0.8 ml) and dropped acetone (1.6 ml) thereto under stirring at ambient temperature. After few minutes, the stirring was stopped and the solution was stood for 1.5 hours at ambient temperature to crystallize. The resulting colorless needles were filtered, washed with 90% aqueous acetone (1 ml×2) and acetone (1 ml×3) and dried for 9 hours under reduced pressure to give colorless needles of 7-[2-ethoxyimino-2-(5-amino-1,2,4-thiadiazol-3-yl)acetamido]-3-(1-pyridiniomethyl)-3-cephem-4-carboxylate acetone adduct monohydrate (syn isomer) (120 mg), mp >155° C. (dec.).

1. waitAfter few minutes
2. customto crystallize
3. filtrationThe resulting colorless needles were filtered
4. washwashed with 90% aqueous acetone (1 ml×2) and acetone (1 ml×3)
5. customdried for 9 hours under reduced pressure