反应详情

Under nitrogen atomosphere, a solution of aluminium chloride (2.65 g) in anisole (5.7 ml) was added dropwise to a solution of diphenylmethyl 7β-[2-(2-aminothiazol-4-yl)-2-(Z)-(trityloxyimino)acetamido]-3-[(1-tritylpyrazol-4-yl)methylthio]-3-cephem-4-carboxylate (3.32 g) in a mixture of anisole (5.7 ml) and nitromethane (22.5 ml) at −24° C. After stirring for 1 hour at the same temperature, the reaction was quenched with 1N hydrochloric acid (22.5 ml). The mixture was poured into a mixture of water and ethyl acetone. The aqueous layer was separated and the organic layer was reextracted with water. The combined aqueous layer was concentrated in vacuo, chromatographed on a HP-20 column (eluent: water-methanol). After the concentration, the resulting precipitate was collected by filtration to afford 7β-[2-(2-aminothiazol-4-yl)-2-(Z)-(hydroxyimino)acetamido]-3-[(pyrazol-4-yl)methylthio]-3-cephem-4-carboxylic acid

1. customthe reaction was quenched with 1N hydrochloric acid (22.5 ml)
2. additionThe mixture was poured into a mixture of water and ethyl acetone
3. customThe aqueous layer was separated
4. concentrationThe combined aqueous layer was concentrated in vacuo
5. customchromatographed on a HP-20 column (eluent: water-methanol)
6. concentrationAfter the concentration
7. filtrationthe resulting precipitate was collected by filtration