New synthesis of benzo[b][1,6]naphthyridines and pyrido[4,3-b]benz[f]azepines from lactim ethers of 3,4-dihydrocarbostyril and 1H-2,3,4,5-tetrahydrobenz[b]azepin-2-one

Abstract

New synthesis of benzo[b][1,6]naphthyridines and pyrido[4,3 b]benz[ f ]azepines from lactim ethers of 3,4 dihydrocarbostyril and 1H 2,3,4,5 tetrahydrobenz[b]azepin 2 oneCondensation of lactim ethers of 3,4 dihydrocarbostyril and 1H 2,3,4,5 tetrahydro benz[b]azepin 2 one with malonodinitrile, cyanoacetamide, and ethyl cyanoacetate gave the corresponding 2 methylidene derivatives. Their reactions with dimethylformamide diethyl acetal followed by cyclization into benzo[b][1,6]naphthyridines and pyrido[4,3 b]benz[ f ]aze pines were studied.

New synthesis of pyrido[4,3-b]indoles (γ-carbolines) on the basis of indolin-2-one lactim ether

“…1 Recently, we have shown that 3,4 dihydro сarbоstyryl and 1H 2,3,4,5 tetrahydrobenz[b]azepin 2 one lactim ethers smoothly reaсt with сyanoaсetiс aсid derivatives to form the сorresponding methylidene de rivatives, whiсh turned out to be convenient starting сompounds for the synthesis of triсyсliс systems, сont aining hydrogenated naphthiridine and pyridoazepine bi cyclic fragments. 2 It seemed interesting to apply this method for the synthesis of tri and tetraсyсliс indole сontaining deriva tives. A complexity of this pathway consisted in the fact that its realization required lactim ether of indolin 2 one (oxindole).…”