Diisopropylethylamine → HCID 68735737, 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, see Example 9), (R)-2-(tert-butoxycarbonylamino)-3-(4-chlorophenyl)propanoic acid (0.024 g, 0.080 mmol) and TBTU (0.0308 g, 0.0961 mmol) in DCM (1 mL) and stirred at room temperature for 1 hour. The reaction was then 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 20 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 the solvent, the resulting residue was purified by chromatography (hexane:ethyl acetate, 1:1) to give (R)-tert-butyl 3-(4-chlorophenyl)-1-(4-(3-methoxy-5-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazin-1-yl)-1-oxopropan-2-ylcarbamate as a solid. The solid was dissolved in DCM (1 mL), and TFA (0.4 mL) was added. The mixture was stirred at room temperature for 2 hours and then 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 (R)-2-amino-3-(4-chlorophenyl)-1-(4-(3-methoxy-5-phenyl-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazin-1-yl)propan-1-one (0.036 g, 79%). MS APCI (+) m/z 491.3 detected.

Provenance & Evidence