Secondary metabolites kurzichalcolactone A and B from Cryptocarya lucida Blume (Lauraceae)

Plants of Cryptocarya (Lauraceae) are known to contain 6-substituted 5,6-dihydro-2-pyrones, flavanoids, alkaloids, and terpenoids. One of endemic plants of Kalimantan forest, C. lucida Blume, has been selected for phytochemical study on its phenolic constituents. Fractionation of the methanol extract of the stem bark of this plant, followed by purification of the phenolic fractions, afforded two chalcone derivatives, named kurzichalcolactones A and B. The structures of both compounds were determined by spectroscopic methods, including UV, IR, 1 H-NMR, 13 C-NMR data, as well as by comparison with those reported data. Cytotoxic evaluation of both compounds against murine leukemia P388 cells showed that their IC 50 to be 6.3 and 17.9 µg/mL, respectively.