Synthesis and anti-inflammatory activities of 4H-chromene and chromeno[2,3-b]pyridine derivatives

Several derivatives of 4H-chromene and chromeno[2,3-b]pyridine were efficiently prepared under microwave irradiation in a one-pot reaction, and their anti-inflammatory activities were evaluated. Six synthetic products (1b, 1c, 1h, 2d, 2j, and 2l) exhibited more powerfully inhibited the production of tumor necrosis factor-α-induced nitric oxide (NO) than quercetin and exhibited comparable cell viability in both human and porcine chondrocytes. In particular, 2d at dosages of 10 and 20 mg/kg had a very potent anti-inflammatory effect by suppressing the formation of carrageenan-induced rat paw edema and prostaglandin E2. The results herein suggest that these compounds may have potential as structural templates in the design and development of new anti-inflammatory drugs.