反应详情

A mixture of 2-(2-amino-5-methylthiazol-4yl)-2-methoxyiminoacetic acid (syn isomer, 2.6 g.), acetic anhydride (31 ml.) and formic acid (13 ml.) was stirred at room temperature for 2 hrs. and then evaporated in vacuo. The residue was dissolved in a mixture of water and ethyl acetate. The ethyl acetate layer was separated, washed with an aqueous solution of sodium chloride, dried over magnesium sulfate, treated with activated charcoal and then filtered. The filtrate was evaporated in vacuo. The oily residue was treated with n-hexane and diisopropyl ether, and the precipitates were collected by filtration to give 2-(2-formamido-5-methylthiazol-4-yl)-2-methoxyiminoacetic acid (syn isomer, 2.8 g.).

1. customand then evaporated in vacuo
2. dissolutionThe residue was dissolved in a mixture of water and ethyl acetate
3. customThe ethyl acetate layer was separated
4. washwashed with an aqueous solution of sodium chloride
5. dry with materialdried over magnesium sulfate
6. additiontreated with activated charcoal
7. filtrationfiltered
8. customThe filtrate was evaporated in vacuo
9. additionThe oily residue was treated with n-hexane and diisopropyl ether
10. filtrationthe precipitates were collected by filtration