1,5-Dihydro-1,5-dioxo-N-1H-tetrazol-5-yl-4H-[1]benzopyrano[3,4-b]pyridine-3-carboxamides and process thereof

摘要

The present invention relates to 1,5-dihydro-1,5-dioxo-N-1H-tetrazol-5-yl-4H-[1]benzopyrano[3,4-b]pyrid ine-3-carboxamides having the following structural formula: I wherein R1 is hydrogen, halogen, hydroxy, lower alkoxy, lower alkyl or nitro and R2 is hydrogen or lower alkyl. These compounds and their pharmaceutically acceptable salts are useful in the management of allergic manifestations such as bronchial asthma, hay fever and the like.