Attempts at new synthesis of 5,11-dihydro-6H-pyrido[2,3-b][1,4]benzodiazepin-6-one

Article abstract of DOI:10.1002/jhet.5570200536

Attempting some new approaches to 5,11-dihydro-6H-pyrido[2,3-b)[1,4]benzodiazepin-6-one (6), compounds 8, 10 and 11 were prepared. Ring enlargement of 4 into 6 failed, as well as condensation of 10 and 11 into ID, which is the potential precursor of pirenzepin (11-[2'-(4'-methylpiperazin-1'-yl)]acetyl derivative of 6) via an envisaged intramolecular Diels-Alder reaction. Model compounds 5 and 13 were prepared and their behaviour in analogous reactions explained the failures of the intended transformations of 4, as well as of condensation of 10 and 11.