A convenient synthesis of new (E)-5-hydroxy-2-styrylchromones by modifications of the Baker–Venkataraman method
Abstract
New 5-hydroxy-2-styrylchromones and 3-cinnamoyl-5-hydroxy-2-styrylchromones have been prepared by modifications of the Baker–Venkataraman method. All compounds were fully characterized using several 1D and 2D NMR techniques. The E stereochemistry of the double bonds of all the 5-hydroxy-2-styrylchromones and the conformational features of those substituted in the 2′ and 2″ positions were unambiguously established by NOE experiments.