Chemical Constituents and Biological Studies of the Leaves of Grevillea robusta

摘要

Three new compounds: Graviquinone (>1), cis-3-hydroxy-5-pentadecylcyclohexanone (>2), and methyl 5-ethoxy-2-hydroxycinnamate (>3), and thirty-eight known compounds were isolated and identified from the leaves of Grevillea robusta. The structures of these compounds were determined by spectroscopic and chemical transformation methods. Graviquinone (>1) showed the strongest cytotoxicity against MCF-7, NCI-H460, and SF-268 cell lines. Methyl 2,5-dihydroxycinnamate (>4), graviphane (>13), and dehydrograviphane (>14) exhibited very potent DPPH scavenging activity compared with α-tocopherol. Methyl 2,5-dihydroxycinnamate (>4) and bis-norstriatol (>17) demonstrated strong inhibition of L-DOPA oxidation by mushroom tyrosinase compared with kojic acid.