Selective Synthesis and Biological Application of Flavonoids

Abstract

Secondary metabolites such as alkaloids, polyphenols, and isoprenoids are produced by plants. From these, flavonoids are one of the most naturally found polyphenol organic compounds. Flavonoids have a wide range of biological uses such as anti-diabetic activity and anti-cancer activity as well as antioxidant properties. This review article presents the various chemical synthetic methods of flavonoids. Flavonoids are prepared from chalcones, coumarin, 1,3-diones, eugenol using cyclic oxidation, Wacker oxidation, Suzuki-Miyaura reaction, and Knoevenagel condensation. Flavonoids can be divided into three main classes such as flavones, isoflavonoids and neoflavonoids (4-arylcoumarins). Flavones are successfully synthesized by Baker and Venkatraman synthesis and Claisen-Schmidt condensation method while Isoflavonoids are prepared using deoxybenzoin, Suzuki-reaction, oxidative rearrengement, and chalcone routes. Neoflavonoids are synthesized from coumarin using Suzuki-Miyaura reaction and Knoevenagel condensation system.