Synthesis and hypoglycemic activity of some substituted flavonyl thiazolidinedione derivatives--fifth communication: flavonyl benzyl substituted 2,4-thiazolidinediones.

A new series of 3-benzyl(p-substituted benzyl)-5-[3'-(4H-4-oxo-1-benzopyran-2-yl)-benzylidene]-2,4-thiazolidinediones (8a-e) were synthesized. These products were prepared by Knoevenagel reaction from 3'-flavone carboxaldehyde and 3-substituted 2,4-thiazolidinediones. In vitro insulinotropic activity was determined for compounds 6a-e, 7a-e, 8b and 8c.