Triethylamine → 1-[1-(thiophen-3-yl)carbonylmethyl-2-oxo-5-pivaloyl-8-methyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepin-3-yl]-3-(3-ethoxycarbonylphenyl)urea

Participants

Reaction Steps

Ethyl 3-aminobenzoate (0.33 g) was dissolved in tetrahydrofuran (20 ml) and cooled on ice. Triphosgene (0.22 g) was added at internal temperature 5° C., triethylamine (0.76 g) was added dropwise thereto over 10 minutes period, the mixture was allowed to come to room temperature,stirred for 10 minutes. A solution of 1-(thiophen-3-yl)carbonylmethyl-2-oxo-3-amino-5-pivaloyl-8-methyl-1,3,4,5-tetrahydro-2H-1,5-benzodiazepine (0.69 g) in tetrahydrofuran (10 ml) was added, the resultant mixture was stirred for one hour. Water was added to the reaction mixture, extracted with methylene chloride, the organic layer was successively washed with water and saturated brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure, the residue was purified by silica gel column chromatography(n-hexane:ethyl acetate=1:1), to thereby obtain 0.86 g of the titled compound as pale brown crystals (Yield: 75%).

Provenance & Evidence