3,5-dichloro-4-((S)-2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)-2-((S)-3-(3-formylbenzoyl)thiazolidine-2-carbonyloxy)ethyl)pyridine 1-oxide (108 mg, 0.162 mmol) was dissolved in DCM (2 ml). Aniline (18.08 mg, 0.194 mmol) and acetic acid (9.26 μL, 0.162 mmol) were added, and the mixture was stirred at RT for 1 hour. Sodium triacetoxyborohydride (51.4 mg, 0.243 mmol) was added, and the mixture was stirred at RT overnight to achieve completion. The reaction mixture was diluted with DCM and extracted with water (2×). The organic phase was dried over Na2SO4 and concentrated under vacuum to give 3,5-dichloro-4-((S)-2-(3-(cyclopropylmethoxy)-4-(difluoromethoxy)phenyl)-2-((S)-3-(3-((phenylamino)methyl)benzoyl)thiazolidine-2-carbonyloxy)ethyl)pyridine 1-oxide (120 mg, 0.161 mmol, 100% yield). The compound was used in the next step without any further purification.
