[Study on substances with antiblastic activity. LIX - Anthramycin and analogs. VIII : synthesis of derivatives of 4H-pyrrolo/1,2-a/[1,5]benzodiazepine].

Preparation of 4H-pyrrolo[1,2-a][1,5]benzodiazepine derivatives related to the antitumoral antibiotic anthramycin, a derivative of 5H-pyrrolo[2,1-c] [1,4]benzodiazepine, is reported. Reaction between 1-(o-acetamidophenyl)-2-dimethylaminomethylpyrrole iodomethylate and potassium cyanide afforded 4,6-dihydro-5H-pyrrolo[1,2-a][1,5]benzodiazepine-5-one, which was then reduced to 5,6-dihydro-4H-pyrrolo[1,2-a][1,5]benzodiazepine by the action of lithium aluminum hydride. Some 6-acylderivatives of the latter compound are also described. The Vilsmeier-Haack reaction on 6-acetyl-5,6-dihydro-4H-pyrrolo[1,2-a][1,5]benzodiazepine furnished the corresponding 1-formyl derivative which was then condensed with ethyl cyanoacetate to give the related compound with the acrylic moiety.