CHEMICAL CONSTITUENTS FROM THE ROOTS OF Garcinia schomburgkiana Pierre

Abstract

Phytochemical investigation of the CH2Cl2 extract from the roots of Garcinia schomburgkiana led to the isolation of two new depsidones, schomburgdepsidones A and B (GS1 and GS2), and one new xanthone, schomburgxanthone A (GS3), along with eight known compounds; oliveridepsidone A (GS4), oliveridepsidone D (GS5), 1,5-dihydroxyxanthone (GS6), nigrolineaxanthone E (GS7), 6-desoxyjacareubin (GS8), aucuparin (GS9), 3-hydroxy-5-methoxybiphenyl (GS10) and methyl-2,6-dihydroxy-4-methoxy-3(3'-methyl-2'-butenyl)-benzoate (GS11). The structures of the three new isolated compounds (GS1–GS3) were elucidated by using 1D- and 2D-NMR spectroscopy. The structures of the known compounds (GS4–GS11) were determined and confirmed by comparison of their 1H and 13C NMR spectroscopic data with previously published data. All 11 compounds were evaluated on the in vitro cytotoxicity against the KB, HeLa S-3, HT-29, MCF-7 and Hep G2 human cancer cell lines, and pancreatic lipase inhibitory activity. The tested compounds mostly showed moderate activities to inactive against the five human cancer cell lines, except for compound GS7 exhibited a good cytotoxicity against the KB, Hela S-3 and MCF-7 cell lines with IC50 values in the range of 3.17–6.07 μM. Compound GS3 showed a good cytotoxic activity against the KB cell line only, with an IC50 value of 8.14 μM. The result of the pancreatic lipase inhibitory activity of 11 compounds possessed moderately active of compounds GS1–GS3, GS7, GS8 and GS11 with IC50 values in the range of 23.71–80.78 μM, while the other tested compounds showed a weak activity (IC50 values >100 μM).