反应详情

Stannous chloride dihydrate (84.6 mg) was added to a solution of 1-ethoxycarbonyloxyethyl 7-[(Z)-2-methoxyimino-2-(thiazol-4-yl)acetamido]-3-(3-methyl-1,2,4-thiadiazol-5-yl)thiomethyl-3-cephem-4-carboxylate-1-oxide (96.6 mg) in dimethylformamide (2 ml), and then acetyl chloride (0.38 ml) was added dropwise to the mixture with stirring while cooling with ice. After further stirring in 20° C. for 15 min, the reaction mixture was poured into a mixture of water (20 ml) and ethyl acetate (15 ml). The ethyl acetate layer was separated and the aqueous layer was extracted twice with ethyl acetate (15 ml). The whole ethyl acetate layer combined was dried over MgSO4, concentrated in vacuo, and the residue was added to petroleum ether (30 ml). The resulting crystals were filtered, washed with petroleum ether, and dried in vacuo to give the title compound (30 mg). ##STR24##

1. temperaturewhile cooling with ice
2. stirringAfter further stirring in 20° C. for 15 min
3. customThe ethyl acetate layer was separated
4. extractionthe aqueous layer was extracted twice with ethyl acetate (15 ml)
5. dry with materialThe whole ethyl acetate layer combined was dried over MgSO4
6. concentrationconcentrated in vacuo
7. additionthe residue was added to petroleum ether (30 ml)
8. filtrationThe resulting crystals were filtered
9. washwashed with petroleum ether
10. customdried in vacuo