Synthesis of new pyrrolo[3,2-l]acridinones and pyrrolo[3,2-c][1,8]naphthyridinones by condensation of methoxybenzenes or phenols with isobutyric aldehyde and o-aminonitriles

A reaction of methoxybenzenes or phenols with isobutyric aldehyde and 2-amino-5-nitro- or 2-amino-4-chlorobenzonitriles in concentrated H2SO4 medium was used for the preparation of new pyrrolo[3,2-l]acridinone derivatives. Analogous reactions using 2-amino-3-pyridinecarbonitrile enabled the synthesis of previously unknown benzo[b]pyrrolo[3,2-c][1,8]naphthyridinones.