反应详情

2-Ethoxyimino-2-(2-formamidothiazol-4-yl)acetic acid (syn isomer) (2.2 g) was added to a solution of phosphorus pentachloride (2.0 g) in dichloromethane (40 ml) at -10° C., and stirred at -5° C. to -10° C. for 1 hour. After the addition of triethylamine (2.0 g), the resulting mixture was stirred at -5° C. for 5 minutes [Solution A]. N-trimethylsilylacetamide (9.8 g) was added to a stirred suspension of 1-[(7-amino-4-carboxy-3-cephem-3-yl)methyl]pyridinium chloride hydrochloride dihydrate (3.0 g) in dry tetrahydrofuran (60 ml), and the mixture was stirred for 20 minutes at 35° C. to 40° C. To the solution was added the solution A at -10° C. and the resulting solution was stirred at the same temperature for 40 minutes. Water and ethyl acetate were added to the reaction mixture at -10° C. and the separated aqueous layer was washed with ethyl acetate and adjusted to pH 4.0 with 10% aqueous solution of sodium hydroxide. The resulting solution was subjected to column chromatography on macroporous non-ionic adsorption resin "Diaion HP-20" (Trademark: Prepared by Mitsubishi Chemical Industries) and eluted with 10% aqueous solution of isopropyl alcohol. The fractions containing the object compound were collected and concentrated and lyophilized to give 7-[2-ethoxyimino-2-(2-formamidothiazol-4-yl)acetamido]-3-(1-pyridiniomethyl)-3-cephem-4-carboxylate (syn isomer) (1.52 g).

1. stirringthe mixture was stirred for 20 minutes at 35° C. to 40° C
2. stirringthe resulting solution was stirred at the same temperature for 40 minutes
3. washthe separated aqueous layer was washed with ethyl acetate
4. customThe resulting solution was subjected to column chromatography on macroporous non-ionic adsorption resin "Diaion HP-20" (Trademark: Prepared by Mitsubishi Chemical Industries)
5. washeluted with 10% aqueous solution of isopropyl alcohol
6. additionThe fractions containing the object compound
7. customwere collected
8. concentrationconcentrated