A new flavan-3-ol dimer from Ficus spragueana leaves and its cytotoxic activity

Background: Isolation and structure elucidation of flavan-3-ol constituents from the leaves of Ficus spragueana and their cytotoxic activity. Materials and Methods: Different open silica gel column chromatographic techniques with different solvent systems were used for the separation of the constituents of the ethyl acetate-soluble fraction of the alcoholic extract of Ficus spragueana leaves. The structures of these compounds were assigned on the basis of spectroscopic analyses and comparison with literature data. MTT colorimetric assay method (Viability assay) was used for the evaluation of cytotoxic activity of compound 1 against human breast cancer (MCF-7) and human liver cancer (HepG2) cell lines. Results: The isolation of one flavan-3-ol dimer and was identified as (-)-afzelechin-(4α→8)-epicatechin 1, and two flavan-3-ol monomers and were identified as (-)-epiafzelechin 2 and (-)-epicatechin 3. Compound 1 was relatively inactive against human breast cancer (MCF-7) cell line at the tested concentrations as compared with the standard. However, at a concentration (50 µg) it was found to give inhibition upon the proliferation of examined human liver (HepG2) tumor cell line. Conclusions: Compound 1 is a new flavan-3-ol dimer and it showed a potent cytotoxic activity against human liver (HepG2) tumor cell line.