反应详情

24.9 g of ethyl 2-(2-amino-4-thiazolyl)-2-[(Z)-[(1-methyl-1H-tetrazol-5-yl)methoxy]imino]-acetate are dissolved in 100 ml of methanol and the solution is treated with 250 ml of 1N aqueous sodium hydroxide solution. The mixture is stirred at room temperature for 12 hours and treated with 150 ml of water. The methanol is subsequently removed under reduced pressure. The aqueous solution is washed with ethyl acetate and treated with 250 ml of 1N aqueous hydrochloric acid. The acid crystallizes upon concentration. The acid is filtered off and, for the removal of water (about 16%), stirred for 6 hours in 350 ml of acetonitrile, filtered and dried. There are obtained 14.2 g of 2-(2-amino-4-thiazolyl)-2-[(Z)-[(1-methyl-1H-tetrazol-5-yl)methoxy]imino]-acetic acid of melting point 185° C.

1. customThe methanol is subsequently removed under reduced pressure
2. washThe aqueous solution is washed with ethyl acetate
3. additiontreated with 250 ml of 1N aqueous hydrochloric acid
4. customThe acid crystallizes upon concentration
5. filtrationThe acid is filtered off and, for the removal of water (about 16%)
6. stirringstirred for 6 hours in 350 ml of acetonitrile
7. filtrationfiltered
8. customdried