Activity of flavonoids by optical studies

Flavonoids are wide spread groups of natural constituents and are present in drugs in the form of mono or diglycosides. Flavonoids, being physiologically active, gained importance in the field of pharmacological and clinical applications. Their structural aspects reveal the activity which can be understood in terms of chemical reactions in the molecules. Optical polarizabilities, diamagnetic susceptibilities and electron-ionization cross sections are the three parameters which reflect their chemical activity and hence the drugs containing these flavonoids. As such the theoretical investigation of these parameters is being taken up at present.