反应详情

Benzenesulphonamide (0.037 g.) was added to a stirred solution of 4-[6-(cyclopentyloxycarbonyl)amino-2,3-dihydrobenz-1,4-oxazin-4-ylmethyl]-3-methoxybenzoic acid (0.1 g.), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.046 g.) and 4-(dimethylamino)pyridine (0.029 g.) in dichloromethane (5 ml.), under an atmosphere of nitrogen. The mixture was stirred for 21 hours and then diluted with dichloromethane. This mixture was washed successively with 1M hydrochloric acid (2×10 ml.), 5% w/v sodium bicarbonate solution (2×10 ml.), and saturated brine (20 ml.). It was then dried (MgSO4) and evaporated. The residue was purified by flash chromatography on silica gel (3 cm. diameter column) eluting with 1:1 v/v ethyl acetate:hexane. The solid obtained was recrystallized from ethyl acetate to give the title compound as a white powder (0.071 g., 54%), m.p. 186°-187° C.

1. washThis mixture was washed successively with 1M hydrochloric acid (2×10 ml.), 5%
2. dry with materialIt was then dried (MgSO4)
3. customevaporated
4. customThe residue was purified by flash chromatography on silica gel (3 cm. diameter column)
5. washeluting with 1:1 v/v ethyl acetate
6. customThe solid obtained
7. customwas recrystallized from ethyl acetate