Sulfuric Acid → 1-(4-cyanophenyl)-5-(3,6-dimethyl-2,4-dioxo-1-(3-trifluoromethylphenyl)-1,2,3,4-tetrahydropyrimidin-5-yl)-1H-pyrazole-4-sulfonamide

Participants

Reaction Conditions

Reaction Steps

To (S)-1-(4-cyanophenyl)-5-(3,6-dimethyl-2,4-dioxo-1-(3-trifluoromethylphenyl)-1,2,3,4-tetrahydropyrimidin-5-yl)-N-(2-hydroxy-1-phenylethyl)-1H-pyrazole-4-sulfonamide (prepared in Example 212) (813 mg) was added in water bath (at 20° C.) concentrated sulfuric acid (30 ml) and the resulting mixture was stirred for fifteen minutes. The mixture was cooled to 0° C. and to the reaction solution was then added water (60 ml) dropwise followed by an addition of chloroform (50 ml×2) such that the intended products were extracted into an organic layer. The organic layer was washed with saturated saline (50 ml), dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: chloroform/methanol) to afford the same product as Example 209, (+)-1-(4-cyanophenyl)-5-(3,6-dimethyl-2,4-dioxo-1-(3-trifluoromethylphenyl)-1,2,3,4-tetrahydropyrimidin-5-yl)-1H-pyrazole-4-sulfonamide (406 mg).

Provenance & Evidence