Diisopropylethylamine → HCID 68758071, compound

Participants

Reaction Steps

DIEA (0.0558 mL, 0.320 mmol) was added to 3-methoxy-5-phenyl-4-(piperazin-1-yl)-1H-pyrazolo[3,4-b]pyridine dihydrochloride (0.034 g, 0.080 mmol), 2-(1H-benzo[d][1,2,3]triazol-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate (0.0308 g, 0.0961 mmol) and (S)-3-(tert-butoxycarbonyl(isopropyl)amino)-2-(4-chlorophenyl)propanoic acid (0.0274 g, 0.080 mmol, see Example B) in DCM (1 mL) and stirred at room temperature for 1 hour. The reaction was concentrated to dryness. The resulting residue was dissolved in THF/MeOH (2 mL, 1:1), and an aqueous LiOH solution (1 mL, 2M) was added. It was stirred for 30 minutes, and then ether (20 mL) was added. The organic layer was separated, washed with brine (10 mL), and dried over sodium sulfate. After removal of solvent, the resulting residue was purified by column chromatography (hexane:ethyl acetate, 1:1) to give (S)-tert-butyl 2-(4-chlorophenyl)-3-(4-(3-methoxy-5-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazin-1-yl)-3-oxopropyl(isopropyl)carbamate as a solid. The solid was then dissolved in DCM (1 mL), and TFA (0.4 mL) was added. The mixture was stirred at room temperature for 2 hours and concentrated to dryness. The resulting residue was dissolved in DCM (0.5 mL), and HCl in ether (1 mL, 2N) was added. The resulting solid was collected by filtration to give (S)-2-(4-chlorophenyl)-3-(isopropylamino)-1-(4-(3-methoxy-5-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazin-1-yl)propan-1-one dihydrochloride (0.029 g, 60%). MS APCI (+) m/z 533.3 detected.

Provenance & Evidence