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Published on: February 28, 2025
Cowaniin, a C-glucosidic ellagitannin dimer linked through catechin from Cowania mexicana
Hideyuki Ito1, Masateru Miyake, Eisei Nishitani
1Department of Pharmacognosy, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Tsushima, Okayama, Japan. hito@cc.okayama-u.ac.jp
Abstract:
A new complex tannin, cowaniin (1) was isolated from the leaves and stems of Cowania mexicana (Rosaceae), and its structure was characterized as novel C-glucosidic tannin dimer linked through (+)-catechin on the basis of spectral and chemical evidence. The inhibitory effect on activation of the Epstein-Barr virus early antigen was assessed for cowaniin. Six known polyphenols and related compounds, including a nitrile glucoside, purshianin, were also characterized.