1,8-Diazabicyclo(5.4.0)undec-7-ene → 3-[(7-fluoroimidazo[1,2-a]quinoxalin-4-yl)amino]propyl (2R)-2-[(tert-butoxycarbonyl)amino]propanoate

Participants

Reaction Conditions

Reaction Steps

To a solution of commercially available (Peakdale) 3-[(7-fluoroimidazo[1,2-a]quinoxalin-4-yl)amino]propan-1-ol (20 mg, 0.08 mmol) and 1,8-diazabicyclo[5.4.0]undec-7-ene (12 μL, 0.08 mmol) in anhydrous dimethylformamide (600 μL) under argon was added dropwise a solution of tert-butyl {(1R)-2-[(2,5-dioxopyrrolidin-1-yl)oxy]-1-methyl-2-oxoethyl}carbamate (22 mg, 0.08 mmol) in anhydrous dimethylformamide (200 μL). The mixture was stirred at 60° C. for 65 h, then diluted with cold water and extracted four times with chloroform and once with chloroform/isopropanol (5:1). The combined organic layers were washed with brine, dried over sodium sulfate, filtered and evaporated. The crude product was purified by preparative TLC (silica, dichloromethane/methanol 20/1) to afford the title compound as a colorless oil (4 mg, 12%).

Provenance & Evidence