Portosin Class of chemical compounds From Wikipedia, the free encyclopedia Portosins are vinylpyranoanthocyanins, a type of blueish phenolic pigments, found in aged port wine.[1] General structure of portosins, with R1 being O-CH3, R2 being O-CH3, OH or H, R3 being glucose, coumaroylglucose or acetylglucose and R4 being catechin, phenol or a procyanidin dimer. See also Wine color References [1]Mateus, N; Oliveira, J; Haettich-Motta, M; De Freitas, V (2004). "New Family of Bluish Pyranoanthocyanins". Journal of Biomedicine & Biotechnology. 2004 (5): 299–305. doi:10.1155/S1110724304404033. PMC 1082895. PMID 15577193. This article about an aromatic compound is a stub. You can help Wikipedia by adding missing information.vte Related Articles