Benzoic acid, 3-(chlorosulfonyl)- → 4-((S)-2-((S)-3-(3-carboxyphenylsulfonyl)thiazolidine-2-carbonyloxy)-2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)ethyl)-3,5-dichloropyridine 1-oxide

Participants

Reaction Steps

3,5-dichloro-4-((S)-2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)-2-((S)-thiazolidine-2-carbonyloxy)ethyl)pyridine 1-oxide (209 mg, 0.390 mmol) was dissolved in pyridine (4 ml). 3-(chlorosulfonyl)benzoic acid (172 mg, 0.781 mmol) was added slowly at 0° C., and the reaction was stirred at RT for 8 hours. The reaction mixture was diluted with HCl 1N, filtered, and the precipitate was dissolved in DCM. The organic phase was washed with HCl 1N (2×) and brine, dried over Na2SO4 and concentrated under vacuum to give 4-((S)-2-((S)-3-(3-carboxyphenylsulfonyl)thiazolidine-2-carbonyloxy)-2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)ethyl)-3,5-dichloropyridine 1-oxide (100 mg, 0.139 mmol, 35.6% yield), that was used in the next step without any further purification.

Provenance & Evidence