Synthesis, antimicrobial activity and molecular docking of novel tetracyclic scaffolds incorporating a flavonoid framework with medium sized oxygen heterocycles.

A convenient approach for the synthesis of novel tetracyclic scaffolds incorporating a flavonoid framework with medium sized heterocyclic rings (eight-, nine-, ten- and eleven-membered rings) containing two oxygen atoms from flavonols through alkylation using different dibromoalkanes was described. The synthesized compounds were established based on the spectral data and X-ray crystal structure for 6c. The synthesized compounds were evaluated for their in vitro antimicrobial activity. Docking studies were carried out for most active two compounds 6f and 6i.