反应详情

A solution of (3RS)-3-{5-[2-(2-o-tolylamino-benzoxazol-6-yl)-acetylamino]-pyrid-2-yl}-butyric acid ethyl ester (0.3 g, Reference Example 1) in methanol (4 mL) was treated with aqueous sodium hydroxide solution (1.5 mL, 1M) and left to stand in a water bath at 40° C. for three hours. The mixture was partially evaporated, diluted with more water and partially evaporated again. The residue was diluted with water (10 mL) and washed with diethyl ether (10 mL). The pH of the aqueous phase was adjusted to 7 by addition of dilute hydrochloric acid. The resulting white solid was filtered then dried and then triturated with boiling acetonitrile to give the title compound (0.06 g) as a white powder, m.p. 195-196° C. (with decomposition). MS: 445 (MH+).

1. waitleft
2. customThe mixture was partially evaporated
3. additiondiluted with more water
4. custompartially evaporated again
5. additionThe residue was diluted with water (10 mL)
6. washwashed with diethyl ether (10 mL)
7. additionThe pH of the aqueous phase was adjusted to 7 by addition of dilute hydrochloric acid
8. filtrationThe resulting white solid was filtered
9. customthen dried
10. customtriturated with boiling acetonitrile