Synthesis and Biological Activity of Chromeno[3,2-]Pyridines.

The review summarizes all synthetic methodologies for the preparation of chromeno[3,2-]pyridines and chromeno[3,2-]quinolines. The proposed approaches are systemized based on ways for the construction of the heterocyclic system. The presence of these compounds in nature and their bioactivity are also discussed. Natural products with an annelated chromeno[3,2-]pyridine fragment are well-known and a number of alkaloids derived from this system as a key core have been recently isolated. These compounds demonstrate antimicrobial, antivirus, and cytotoxic activities, making chromeno[3,2-]pyridine structural motifs promising for medicinal chemistry.