反应详情

To the ester of Example 4, Step B (0.5 g, 1.6 mmol) was added 10 ml MeOH, 0.4 ml 1N HCl and 0.37 ml H2O. The mixture was stirred one minute followed by addition of CH3SO2NHNH2 all at once. After overnight stirring, the MeOH was evaporated and additional water was added. This aqueous phase was twice extracted with CH2Cl2. The organic phase was concentrated to a crude solid and purified by flash chromatography using CH2Cl2 --EtOAc 95-5 as eluent. The product 0.33 g, was obtained as a solid m.p. 80°-82° C.

1. stirringAfter overnight stirring
2. customthe MeOH was evaporated
3. additionadditional water was added
4. extractionThis aqueous phase was twice extracted with CH2Cl2
5. concentrationThe organic phase was concentrated to a crude solid
6. custompurified by flash chromatography