反应详情

Sodium hydride (60% dispersion in oil; 0.094 g) was added to a solution of 2-amino-5-bromo-3-methoxypyrazine (0.159 g) in dimethoxyethane (4 ml). The solution was stirred for 10 minutes and then 4-nitrophenyl 4'-isobutyl-2-biphenylsulphonate (0.321 g) was added. The solution was allowed to stand for 5 hours and then water (20 ml) was added. 2M Hydrochloric acid (2 ml) was added and the mixture was extracted with ethyl acetate (2×30 ml). The extracts were dried (MgSO4) and volatile material was removed by evaporation. The residue was purified by elution with ethyl acetate/hexane (1:3 v/v) through a silica gel Mega Bond Elut column. The resulting solid was recrystallised from a mixture of ether and hexane to give N-(5-bromo-3-methoxy-2-pyrazinyl)-4'-isobutyl-2-biphenylsulphonamide (0.09 g), m.p. 154°-156° C.; 1H NMR (d6 -DMSO): 0.9 (d,6H), 1.8-2.0 (m,1H), 2.5 (d,2H), 3.85 (s,3H), 7.1 (s,4H), 7.3 (d,1H), 7.5-7.7 (m,2H), 7.8 (br s,1H), 8.05 (d,1H), 10.2-10.3 (br, 1H); mass spectrum (+ve FAB, methanol/NBA): 478 (M+H)+.

1. waitto stand for 5 hours
2. extractionthe mixture was extracted with ethyl acetate (2×30 ml)
3. dry with materialThe extracts were dried (MgSO4) and volatile material
4. customwas removed by evaporation
5. customThe residue was purified by elution with ethyl acetate/hexane (1:3 v/v) through a silica gel Mega Bond Elut column
6. customThe resulting solid was recrystallised from a mixture of ether and hexane