反应详情

Conc. hydrochloric acid (4.1 g) was added to a solution of trifluoroacetic acid salt of 7β-[2-(2-formamidothiazol-4-yl)-2-(2-cyclopenten-1-yloxyimino)acetamido]-3-(2-methyl-1-pyrazolio)methyl-3-cephem-4-carboxylate (A isomer) (syn isomer) (5.8 g) in methanol (60 ml), and the mixture was stirred at ambient temperature for 2 hours. To the reaction mixture was added water (60 ml) and adjusted to pH 2.0 with 5% aqueous solution of sodium bicarbonate. The separated aqueous solution was subjected to column chromatography on macroporous non-ionic adsorption resin "Diaion HP-20" (120 ml) and eluted with 30% aqueous solution of methanol. The fractions containing the object compound were collected and concentrated in vacuo, then lyophilized to give 7β-[2-(2-aminothiazol-4-yl)-2-(2-cyclopenten-1-yloxyimino)-acetamido]-3-(2-methyl-1-pyrazolio)methyl-3-cephem-4-carboxylate (A isomer) (syn isomer) (1.1 g).

1. washeluted with 30% aqueous solution of methanol
2. additionThe fractions containing the object compound
3. customwere collected
4. concentrationconcentrated in vacuo