Diisopropylethylamine → (S)-tert-butyl 2-(4-chlorophenyl)-3-(4-(5-(3-fluorophenyl)-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazin-1-yl)-3-oxopropyl(isopropyl)carbamate

Participants

Reaction Steps

DIEA (d 0.742; 0.0790 mL, 0.454 mmol) was added to a solution of 5-(3-fluorophenyl)-4-(piperazin-1-yl)-1H-pyrazolo[3,4-b]pyridine dihydrochloride (0.070 g, 0.113 mmol), (S)-3-(tert-butoxycarbonyl(isopropyl)amino)-2-(4-chlorophenyl)propanoic acid (0.0388 g, 0.113 mmol, see Example B) and TBTU (0.0437 g, 0.136 mmol) in DCM (1 mL) and stirred at room temperature for 18 hours. The mixture was directly loaded onto a silica column and purified by chromatography (hexane:ethyl acetate, 1:1) to give (S)-tert-butyl 2-(4-chlorophenyl)-3-(4-(5-(3-fluorophenyl)-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazin-1-yl)-3-oxopropyl(isopropyl)carbamate as a solid. The solid was dissolved in DCM (1 mL), and TFA (0.2 mL) was added. The mixture was stirred at room temperature for 1 hour 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 (S)-2-(4-chlorophenyl)-1-(4-(5-(3-fluorophenyl)-1H-pyrazolo[3,4-b]pyridin-4-yl)piperazin-1-yl)-3-(isopropylamino)propan-1-one dihydrochloride (0.022 g, 32%). MS APCI (+) m/z 521.4 detected.

Provenance & Evidence