New synthesis of 2,4-diamino-10-(4-bromo-phenylamino)-10H-9-oxa-1-aza

Benzopyrano[2,3-b]pyridine is an important privileged medicinal scaffold. In this work, the three-component synthesis of 2,4-diamino-10-(4-bromo-phenylamono)-10H-9-oxa-1-aza-anthracene-3-carbonitrile (4), 2,4-diamino-10-p-tolylamino-10H-9-oxa-1-anthracec-3- carbonitrile (5) and 2-(2-amino-3-cyano-4H-chromen-4-yl)-malononitrile (6) from the reaction of salicylaldehyde (1) with p-bromobenzaniline or p-tolylamine (3) in presence of 2 equiv of malononitrile (2), is described.