Diisopropylethylamine → tert-butyl ((3R,4R,5S)-4-{[tert-butyl(dimethyl)silyl]oxy}-1-{5-[({6-[2,6-difluoro-4-(1-hydroxy-1-methylethyl)phenyl]-5-fluoropyridin-2-yl}carbonyl)amino]-2,3-dihydrofuro[2,3-b]pyridin-4-yl}-5-methylpiperidin-3-yl)carbamate

Participants

Reaction Steps

A mixture of tert-butyl ((3R,4R,5S)-1-(5-amino-2,3-dihydrofuro[2,3-b]pyridin-4-yl)-4-{[tert-butyl(dimethyl)silyl]oxy}-5-methylpiperidin-3-yl)carbamate (200 mg, 0.418 mmol), 6-[2,6-difluoro-4-(1-hydroxy-1-methylethyl)phenyl]-5-fluoropyridine-2-carboxylic acid (130 mg, 0.418 mmol), HATU (318 mg, 0.836 mmol) in DMF (1.5 mL) and DIPEA (218 μL, 1.25 mmol) was stirred at room temperature for 2 h. After quenched with water, the mixture was extracted with EtOAc (2×). The combined organic phases were washed with brine, dried over Na2SO4, and concentrated. The residue was purified by purified by column chromatography on silica gel using CombiFlash® apparatus eluting with EtOAc/hexanes (50-100%), to yield an amide intermediate, tert-butyl ((3R,4R,5S)-4-{[tert-butyl(dimethyl)silyl]oxy}-1-{5-[({6-[2,6-difluoro-4-(1-hydroxy-1-methylethyl)phenyl]-5-fluoropyridin-2-yl}carbonyl)amino]-2,3-dihydrofuro[2,3-b]pyridin-4-yl}-5-methylpiperidin-3-yl)carbamate.

Provenance & Evidence