反应详情

A mixture of benzhydryl 7-amino-3-[(Z)-2-(2-pyridyl) -vinylthio]-3-cephem-4-carboxylate (600 ml) and bis-(trimethylsilyl)urea (981 mg) in methylene chloride (6 ml) was stirred at 30°~35° C. for 30 minutes to give a clear solution. To the clear solution was added 2-allyloxyimino-2-(5-amino-1,2,4-thiadiazol-3yl) acetyl chloride monohydrochloride (syn isomer) (480 mg) at -20° C. and the mixture was stirred for 30 minutes at -10°~-15° C. The mixture was poured into a mixture of chloroform and water. The organic layer was separated and concentrated in vacuo to give a residue. The residue was dissolved in a mixture of tetrahydrofuran, ethyl acetate and dilute aqueous solution of sodium bicarbonate. The organic layer was separated, washed with dilute aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in turn, dried over magnesium sulfate and concentrated in vacuo, and the residue was triturated with diisopropyl ether to give benzhydryl 7-[2-allyloxyimino-2-(5-amino-1,2,4-thiadiazol-3-yl) -acetamido]-3-[(Z)-2-(2-pyridyl)vinylthio]-3-cephem-4-carboxylate (syn isomer) (848 mg).

1. customto give a clear solution
2. stirringthe mixture was stirred for 30 minutes at -10°~-15° C
3. customThe organic layer was separated
4. concentrationconcentrated in vacuo
5. customto give a residue
6. customThe organic layer was separated
7. washwashed with dilute aqueous solution of sodium bicarbonate
8. dry with materiala saturated aqueous solution of sodium chloride in turn, dried over magnesium sulfate
9. concentrationconcentrated in vacuo
10. customthe residue was triturated with diisopropyl ether