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-carbonyl)oxy)ethyl)pyridine 1-oxide hydrochloride (Intermediate 9 above described) (400 mg, 0,699 mmol) was dissolved in Pyridine (2 ml). 3-(chlorosulfonyl)benzoic acid (463 mg, 2,098 mmol) was added at 0° C., and the reaction was warmed at room temperature for 4 hrs to achieve completion. The reaction mixture was quenched with HCl 1N, and the precipitate was washed with HCl 1N, dissolved in DCM and the organic phase was washed with HCl 1N, water and brine, dried over Na2SO4 and concentrated under vacuum to give 4-((S)-2-(((S)-3-((3-carboxyphenyl)sulfonyl)thiazolidine-2-carbonyl)oxy)-2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)ethyl)-3,5-dichloropyridine 1-oxide (352 mg, 0.490 mmol, 70% yield).

Provenance & Evidence