Trifluoroacetic acid → N-[4-[(3S)-3-aminopiperidin-1-yl]-7-hydroxy-6,7-dihydro-5H-cyclopenta[b]pyridin-3-yl]-6-(2,6-difluoro-4-methylsulfonylphenyl)-5-fluoropyridine-2-carboxamide

Participants

Reaction Steps

4-{(3S)-3-[(tert-Butoxycarbonyl)amino]piperidin-1-yl}-3-[({6-[2,6-difluoro-4-(methylsulfonyl)phenyl]-5-fluoropyridin-2-yl}carbonyl)amino]-6,7-dihydro-5H-cyclopenta[b]pyridin-7-yl acetate (11.0 mg, 0.0156 mmol) was dissolved in MeOH (0.04 mL) and THF (0.20 mL), then 1.0 M aq. NaOH (0.062 mL, 0.062 mmol) was added. The reaction mixture was stirred at room temperature for 30 min. The organic solvents and trace of water were removed under vacuum to give a crude intermediate. The intermediate was dissolved in DCM (0.16 mL) and TFA (0.16 mL, 2.1 mmol) was then added. The reaction mixture was stirred at room temperature for 30 min. The solution was concentrated under reduced pressure and the residue was diluted with MeOH, filtered and purified by preparative LC-MS (XBridge™ preparative C18 5 μm OBD™ column, 30×10 mm, 60 mL/min., eluting with a gradient of MeCN and water with 0.1% NH4OH) to give both diastereoisomers of the title compound as white powders. On analytical HPLC (Waters SunFire™ C18, 2.1×50 mm, 5 μm; flow rate 3 mL/min.; injection volume 2 μL; gradient from 2 to 80% B in 3 minutes (A=water with 0.025% TFA, B=MeCN)), the diastereoisomers had the following properties:

Provenance & Evidence