反应详情

A mixture of ethyl 2-(2-amino-5-methylthiazol-4-yl)-2-methoxyiminoacetate (syn isomer, 4.0 g.), 2N-aqueous sodium hydroxide (25 ml.), ethanol (30 ml.) and tetrahydrofuran (15 ml.) was stirred at room temperature for 75 minutes. The reaction mixture was adjusted to pH 6 with hydrochloric acid, and the organic solvent was distilled off in vacuo. The remaining aqueous solution was washed with ethyl acetate and adjusted to pH 3 with hydrochloric acid. The resultant precipitates were collected by filtration, washed with water and dried to give 2-(2-amino-5-methylthiazol-4-yl)-2-methoxyiminoacetic acid (syn isomer, 2.6 g.).

1. distillationthe organic solvent was distilled off in vacuo
2. washThe remaining aqueous solution was washed with ethyl acetate
3. customThe resultant precipitates
4. filtrationwere collected by filtration
5. washwashed with water
6. customdried