反应详情

To a solution of 0.3 g (0.57 mmol) of 6-(4-benzyl-5-oxo-2,5-dihydro-1H-pyrazol-1-yl)-N-{(1R,3S)-3-[(benzyloxy)methyl]cyclopentyl}pyridine-3-sulfonamide in 2 mL of DCM cooled to −78° C. are added 1.7 mL of boron tribromide. The temperature is then allowed to rise to 0° C. and stirring is continued for 1 hour at 0° C. 10 mL of MeOH are then added at −10° C. and the medium is concentrated under reduced pressure. The medium is taken up in 100 mL of DCM, washed successively with saturated NaHCO3 solution (2×20 mL) and brine (20 mL), dried over Na2SO4, concentrated under reduced pressure and then purified by chromatography on a column of silica gel, eluting with a 90/10 DCM/MeOH mixture. 126 mg of 6-(4-benzyl-5-oxo-2,5-dihydro-1H-pyrazol-1-yl)-N-[(1R,3S)-3-(hydroxymethyl)cyclopentyl]-N-methylpyridine-3-sulfonamide are obtained in the form of a powder.

1. customto rise to 0° C.
2. concentrationthe medium is concentrated under reduced pressure
3. washwashed successively with saturated NaHCO3 solution (2×20 mL) and brine (20 mL)
4. dry with materialdried over Na2SO4
5. concentrationconcentrated under reduced pressure
6. custompurified by chromatography on a column of silica gel
7. washeluting with a 90/10 DCM/MeOH mixture