反应详情

A solution of (3R,4S)-4-amino-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile (2.40 g) and dimethyl N-cyanoimidodithiocarbonate [(CH2C=C--N--] (1.61 g) in pyridine (12 ml) was stirred at 80° C. for 10 hours, and then concentrated in vacuo. The residue was dissolved in ethyl acetate and washed with 5% aqueous hydrochloric acid, and brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated in vacuo. The residue was subjected to column chromatography on silica gel (48 g) and eluted with a mixture of chloroform and methanol (20:1). The fractions containing the object compound were combined and concentrated in vacuo to give (3R,4S)-4-(3-cyano-2-methyl-1-isothioureido)-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile (2.17 g).

1. concentrationconcentrated in vacuo
2. dissolutionThe residue was dissolved in ethyl acetate
3. washwashed with 5% aqueous hydrochloric acid, and brine
4. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
5. concentrationconcentrated in vacuo
6. washeluted with a mixture of chloroform and methanol (20:1)
7. additionThe fractions containing the object compound
8. concentrationconcentrated in vacuo