反应详情

To a solution of di(trifluoroacetic acid) salt of 7β-amino-3-(4-formamido-2-methyl-1-pyrazolio)methyl-3-cephem-4-carboxylate (4.0 g) and N-(trimethylsilyl)acetamide (9.29 g) in tetrahydrofuran (60 ml) was added methanesulfonyl (Z)-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-carboxymethoxyiminoacetate (2.07 g) under ice-cooling. The mixture was stirred for 1 hour at ambient temperature and then the resulting mixture was added dropwise to diisopropyl ether. Thus produced precipitate was collected by filtration, dissolved in water and then subjected to column chromatography on macroporous non-ionic adsorption resin, Diaion HP-20 (Trademark: manufactured by Mitsubishi Chemical Industries). The desired product was eluted with 10% aqueous isopropyl alcohol solution, and then lyophilized to give 7β-[2-(5-amino-1,2,4-thiadiazol-3-yl)-2-carboxymethoxyiminoacetamido]-3- (4-formamido-2-methyl-1-pyrazolio)methyl-3-cephem-4-carboxylate (syn isomer 0.714 g).

1. temperaturecooling
2. filtrationThus produced precipitate was collected by filtration
3. dissolutiondissolved in water
4. washThe desired product was eluted with 10% aqueous isopropyl alcohol solution