The recent upsurge of interest in the flavonoids, particularly in the use of these compounds in the treatment of numerous clinical disorders, has prompted the compilation of this review. No attempt has been made to be all-inclusive; rather, the review concentrates on a few well-documented findings derived from animal studies for use in the interpretation of the more controversial, less rigidly designed therapeutic reports. An excellent detailed review of several aspects of the subject of flavonoids has recently appeared.1
Chemistry
The flavonoids are carbon-hydrogen-oxygen compounds that are widely distributed in nature as pigments in flowers, fruits, tree barks, and vegetables. The most important commercial source of these compounds is citrus rind. Structurally, the flavone nucleus consists of a benzenoid ring fused to a γ-pyrone moiety. A second benzenoid ring is attached to the carbon adjacent to the ring oxygen of the pyrone (see figure). Naturally occurring flavonoids contain hy