Appearance:A crystalline solid
(−)-Catechin is a diastereoisomer of catechin having a trans 2S,3R configuration at the chiral center. Catechins, in general, are polyphenolic flavonoids that can be isolated from a variety of natural sources including tea leaves, grape seeds, and the wood and bark of trees such as acacia and mahogany. Catechins are potent antioxidants that inhibit the free radical-induced oxidation of isolated LDL by AAPH (Item No. 82235). Catechins and other related procyanidin compounds have antitumor activity when tested in a two-stage mouse epidermal carcinoma model employing topical application.