Larvicidal activity of lansiumamide B from the seeds of Clausena lansium against Aedes albopictus (Diptera: Culicidae)

The larvicidal activity of crude petroleum ether, toluene, n -butanol, ethyl acetate, acetone, and methanol extracts of the seeds of Clausena lansium was assayed for their toxicities against the early fourth instar larvae of Aedes albopictus . The larval mortality was observed after 24-h exposure. The LC 50 value of petroleum ether extract was 22.99 ppm, showing the best larvicidal activity among all six solvent extracts. A cinnamon amide compound lansiumamide B ( N -methyl- N - cis -styrylcinnamamide) was isolated from the petroleum ether extract by column chromatographic method, which exhibited a strong larvicidal activity against the early fourth instar larvae of A . albopictus with LC 50 and LC 90 values of 0.45 and 2.19 ppm, respectively. The structure was elucidated by 1 H NMR, 13 C NMR spectral data. The larvicidal activity against mosquito of lansiumamide B from the seed of C . lansium was evaluated for the first time.