Synthesis of 5H-10,11-dihydropyrazolo[5,1-c]-[1,4]benzodiazepinederivatives. II

Ethyl 3(5)-formylpyrazole-5(3)-carboxylate, 2-nitrobenzyl bromide or 2-nitrobenzoyl chloride are the starting basic materials to prepare with a few reaction steps, pyrazolo5,1-c]1,4]benzodiazepines bearing at position 2 a substituted propionic chain ( 7–9 ) or bearing at position 5 a carbonyl group ( 12 ). Compounds 7–9, 12 are to be considered aza analogs of the antitumor antibiotic antramycin.