CHEMICAL CONSTITUENTS AND CYTOTOXICITY FROM THE ROOTS OF Microcos tomentosa Smith., Garcinia cowa Roxb. AND Dalbergia velutina Benth.

Abstract

A new 3β-O-vanilloyl-taraxerol, microcisin (2.1) and eight known compounds (2.2-2.9) were isolated from the roots of M. tomentosa. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their cytotoxicity against KB and HeLa cell lines. Compounds 2.1, 2.3 and 2.5 showed moderate cytotoxicity against KB cell lines with IC50 values of 24.98, 28.06 and 22.57 µM, respectively. On the other hand, compound 2.3 showed moderate cytotoxicity against HeLa cells with an IC50 value of 29.38 µM. Three new xanthones, kaennacowanols A-C (3.1-3.3) together with nineteen known xanthones (3.4-3.22) were isolated from the roots of G. cowa. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their cytotoxicity against KB and HeLa cell lines. Compounds 3.17 and 3.22 showed good cytotoxicity against KB cell with IC50 values of 7.97 and 9.10 µM, respectively. On the other hand, compound 3.15 showed good cytotoxicity against HeLa cell with IC50 value of 9.34 µM. Three new pterocarpans, velucarpins A-C (4.1-4.3), three new isoflavanes, kaennavelutinols A-C (5.1-5.3) and a new isoflavone glycoside, kaennavelutinose (6.1) together with eleven known compounds including three known pterocarpans (4.4-4.6), two known isoflavanes (5.4-5.5) and six known isoflavones (6.2-6.7) were isolated from the roots of D. velutina. Their structures were determined by spectroscopic analysis. All isolated compounds were evaluated for their cytotoxicity against KB and HeLa cell lines. Compounds 4.3, 4.5, 5.3 and 5.5 showed good cytotoxicity against KB and HeLa cells with IC50 values of 8.22, 8.09, 8.29, 3.47 µM and 5.99, 8.69, 9.54, 5.17 µM, respectively.