Procyanidin A2 Explained

Procyanidin A2 is an A type proanthocyanidin.

It is found in avocado,^[1] chestnut,^{[2] [3]} cranberry juice concentrate,^[4] lychee fruit pericarp,^[5] peanut^[4] skins,^[6] Cinchona cortex, cinnamon cortex, Urvillea ulmaceae,^[7] and Ecdysanthera utilis.^[8]

Synthesis

Procyanidin B2 can be converted into procyanidin A2 by radical oxidation using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals under neutral conditions.^[9]

References

• Wen . LR . Wu . D . Jiang . YM . Prasad . KN . Lin . S . Jiang . GX . He . JR . Zhao . MM . Luo . W . Yang . B . 2014 . Identification of flavonoids in litchi (Litchi chinensis Sonn.) leaf and evaluation of anticancer activities . Journal of Functional Foods . 6 . 555–563 . 10.1016/j.jff.2013.11.022 .

Notes and References

1. http://www.liberherbarum.com/Minor/UK/IN3412.htm Proanthocyanidin-A-2 on liberherbarum.com
2. Proanthocyanidin-A2: a new polyphenol . Facino . R. Maffei . Carini . M. . Brambilla . A. . Bombardelli . E. . Morazzoni . P. . 1996 . Cosmetics & Toiletries.
3. 21803362 . 10.1016/j.chroma.2011.07.024 . 1218 . 42 . Structural analysis of A-type or B-type highly polymeric proanthocyanidins by thiolytic degradation and the implication in their inhibitory effects on pancreatic lipase . 2011 . J Chromatogr A . 7704–12 . Kimura . H . Ogawa . S . Akihiro . T . Yokota . K.
4. Determination of Proanthocyanidin A2 Content in Phenolic Polymer Isolates by Reversed-Phase High Performance Liquid Chromatography . Koerner Jayma, Hsu Victor, Lee Jungmin, Kennedy, James . 2009 . Journal of Chromatography A . 1216 . 1403–1409 . 10.1016/j.chroma.2008.12.086 . 19168185 . 9.
5. Sarni-Manchado P, Le Roux E, Le Guerneve C, Lozano Y, Cheynier V. Phenolic composition of litchi fruit pericarp" J Agric Food Chem 2000;48(12):5995-6002.
6. A-type proanthocyanidins from peanut skins . Hongxiang Lou . Yamazaku Y. . Sasaku T. . Uchida M. . Tanaka H. . Oka S. . 1999 . Phytochemistry . 51 . 2 . 297–308 . 10.1016/S0031-9422(98)00736-5.
7. 10.1080/13880200902933336 . Free radical scavenging activity and chemical constituents of Urvillea ulmaceae . 2009 . Dias . Suziane A. . Cardoso (Gazio) . Flávia P. . Santin . Silvana M. O. . Da Costa . Willian F. . Vidotti . Gentil J. . De Souza . Maria Conceição . Sarragiotto . Maria Helena . Pharmaceutical Biology . 47 . 8 . 717–720. 54906659 .
8. 10.1021/np010414l . Immunomodulatory Proanthocyanidins from Ecdysantherautilis . 2002 . Lin . Lie-Chwen . Kuo . Yuh-Chi . Chou . Cheng-Jen . Journal of Natural Products . 65 . 4 . 505–8 . 11975489.
9. Kondo . Kazunari . Kurihara . Masaaki . Fukuhara . Kiyoshi . Tanaka . Takashi . Suzuki . Takashi . Miyata . Naoki . Toyoda . Masatake . 2000 . Conversion of procyanidin B-type (catechin dimer) to A-type: evidence for abstraction of C-2 hydrogen in catechin during radical oxidation . Tetrahedron Letters . 41 . 4. 485–488 . 10.1016/S0040-4039(99)02097-3 .