Novel antiallergic catechin derivatives isolated from oolong tea.

@article{Sano1999NovelAC,
  title={Novel antiallergic catechin derivatives isolated from oolong tea.},
  author={M. Sano and M. Suzuki and T. Miyase and K. Yoshino and M. Maeda-Yamamoto},
  journal={Journal of agricultural and food chemistry},
  year={1999},
  volume={47 5},
  pages={
          1906-10
        }
}
Two catechin derivatives (C-1 and C-2) with potent antiallergic activity were isolated from Taiwanese oolong tea by HPLC techniques. From NMR and FAB-MS analyses, the structures of C-1 and C-2 were elucidated as (-)-epigallocatechin 3-O-(3-O-methyl)gallate and (-)-epigallocatechin 3-O-(4-O-methyl)gallate, respectively. The oolong tea leaves contained 0.34% (dry weight) C-1 and 0.20% C-2. Traces of C-2 were detected in only 1 of 15 varieties of green tea tested. C-1 was detected in 13 of 15… Expand
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