Triethylamine → N-[2-(4-diphenylmethylpiperazin-1-yl)ethyl]-7-methyl-10-(2,3-dimethylpentanoylamino)-4-oxo-4H-pyrimido[2,1-a]isoquinoline-3-carboxamide

Participants

Reaction Steps

To a stirred mixture containing 10-(2,3-dimethylpentanoylamino)-7-methyl-4-oxo-4H-pyrimido[2,1-a]isoquinoline-3-carboxylic acid (455 mg), triethylamine (0.174 ml) and dry dichloromethane (70 ml) was added slowly ethyl chloroformate (0.12 ml) at 0° C. under an inert atmosphere. After being stirred for 2 hours, a solution of 2-(4-diphenylmethyl-1-piperazinyl)-ethylamine (359 mg) in dry dichloromethane (10 ml) was added dropwise to the reaction mixture at 5° C. After stirring was continued for 12 hours at room temperature, the mixture was concentrated under reduced pressure. The residue was subjected to a column chromatography on silica gel with chloroform-methanol. The eluate was concentrated in vacuo to give residue, which was recrystallized from chloroform-ether to give N-[2-(4-diphenylmethylpiperazin-1-yl)ethyl]-7-methyl-10-(2,3-dimethylpentanoylamino)-4-oxo-4H-pyrimido[2,1-a]isoquinoline-3-carboxamide (0.59 g).

Provenance & Evidence