A novel symmetrical pyrano-3-deoxyanthocyanidin from a Sorghum species

Polyphenols are widespread components of higher plants. Sorghum is rich in polyphenols and known to contain a specific type, 3-deoxyanthocyanins, many of which remain uncharacterised. Here we report the structural determination of a new pigment isolated from red Sorghum bicolor var. bicolor (Moench) and characterised as 8-hydroxy-2-(4'-hydroxyphenyl)-5-(4 ''-hydroxyphenyl)-pyrano[4,3,2-de]1-ben-zopyrylium by MS, UV-vis and 2D NMR spectroscopy. This new symmetrical pyrano-3-deoxyanthocyanidin, containing apigeninidin as a base unit, displays structural features responsible for higher stability as compared to corresponding anthocyanins. (C) 2010 Phytochemical Society of Europe. Published by Elsevier B. V. All rights reserved.