Flavonoids (or bioflavonoids) are a class of plant and fungus secondary metabolites. Chemically, flavonoids have the general structure of a 15-carbon skeleton, which consists of two phenyl rings (A and B) and a heterocyclic ring (C). This carbon structure can be abbreviated C6-C3-C6. Its backbone is 2-phenyl-1,4-benzopyrone. Flavonoids are served as the major active ingredients in traditional Chinese herbal medicines. Several lines of evidence support that flavonoids have impacts on many aspects of human health, including anti-tumor, anti-oxidative, antibacterial, anti-inflammation, and cardiovascular protective effects. The mechanism of action involves scavenging free radicals, down-regulating several inflammatory mediators, inhibiting energy metabolism, stimulating enzymatic activity of DNA-dependent RNA polymerase 1 and subsequent biosynthesis of RNA and protein, inhibiting biosynthesis of protein cytokines, and regulating cell cycle, etc.

TargetMol’s Flavonoid Natural Product Library collects 517 flavonoids derived from many traditional Chinese medicine such as Ginkgo, Radix Sophorae Flavescentis, Radix Astragali, Lonicera japonica, Epimedii Folium, etc. Compounds in the library involve multiple physiological functions, such as Rutin and Quercetin have antiinflammatory, analgesic, antioxidant, and decreasing blood pressure effects; Hesperidin has antioxidant and anti-inflammatory properties; Luteolin, Baicalein, and Baicalin all have antibacterial effects; Genistein has been identified as angiogenesis inhibitors, and found to inhibit the uncontrolled cell growth of cancer.