3526. EGCG

Nomenclature

CAS number: 989-51-5
3,4,5-Trihydroxybenzoic acid, (2R,3R)-3,4-dihydro-5,7-dihydroxy-2-(3,4,5-trihydroxyphenyl)-2H-1-benzopyran-3-yl ester; (-)-epigallocatechin 3-O-gallate; (-)-epigallocatechol gallate.
C22H18O11; mol wt 458.37.
C 57.65%, H 3.96%, O 38.40%.

Description and references

Polyphenolic constituent of tea; inhibits tumor promotion. Indirectly inhibits AhR (aryl hydrocarbon receptor) transcription activation by directly binding to the C-terminus of hsp90, an AhR chaperone protein. Initial identification and isoln from green tea: M. Tsujimura, Bull. Agric. Chem. Soc. Jpn. 6, 70 (1930); C.A. 25, 3637 (1931); and crystallization: L. Vuataz et al., J. Chromatogr. 2, 173 (1959). Oxidation during tea fermentation: P. Coggon et al., J. Agric. Food Chem. 21, 727 (1973). HPLC/MS extraction from black tea: R. G. Bailey et al., J. Sci. Food Agric. 66, 203 (1994). HPLC determn in plasma and urine: M.-J. Lee et al., Cancer Epidemiol. Biomarkers Prev. 4, 393 (1995). Antitumor promoting activity: S. Yoshizawa et al., Phytother. Res. 1, 44 (1987); T. Yamane et al., Cancer Res. 55, 2081 (1995). Inhibition of metastasis in mice: S. Taniguchi et al., Cancer Lett. 65, 51 (1992). Modulation of endocrine systems and food intake: Y.-H. Kao, et al., Endocrinology 141, 980 (2000). Inhibition of AhR transcription by binding to hsp90: C. M. Palermo et al., Biochemistry 44, 5041 (2005).

Chemical structure

Properties

White crystals from water, mp 218°. [α]D -185 ±2°(ethanol). uv max (ethanol): 275 nm (ε 11500).