55626-24-9Relevant academic research and scientific papers
A-type proanthocyanidins from peanut skins
Lou, Hongxiang,Yamazaki, Yoshimitsu,Sasaki, Tsutomu,Uchida, Masaru,Tanaka, Hideoki,Oka, Syuichi
, p. 297 - 308 (2007/10/03)
Six A-type proanthocyanidins were isolated from the water-soluble fraction of peanut skins. On the basis of spectral data, reductive cleavage with sodium cyanoborohydride, and chiral HPLC analysis, three new compounds, epicatechin-(2β → O → 7, 4β → 6)-catechin, epicatechin-(2β → O → 7, 4β → 6)-ent-catechin and epicatechin-(2β → O → 7, 4β → 6)-ent- epicatechin were unambiguously identified, together with the three known compounds, proanthocyanidin A-1, proanthocyanidin A-2 and epicatechin-(2β → O → 7, 4β → 8)-ent-epicatechin. 13C NMR chemical shift rules to distinguish between [2 → O → 7, 4 → 8] and [2 → O → 7,4 → 6] double- linked heptamethyl ethers of A-type proanthocyanidins are proposed. Bioassay experiments showed that these six compounds possess substantial activity against hyaluronidase.
Tannins and Related Compounds. L. Structures of Proanthocyanidin A-1 and Related Compounds
Nonaka, Gen-Ichiro,Morimoto, Satoshi,Kinjo, Jun-Ei,Nohara, Toshihiro,Nishioka, Itsuo
, p. 149 - 155 (2007/10/02)
The structures of proanthocyanidin A-1 (2) and two related proanthocyanidins, tentatively named A-4 (3) and A-5' (4), have been established unambiguously on the basis of spectroscopic evidence and chemical correlations with the structurally known proantho
