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Dodonaea viscosa (Linn.) Jacq. (Sapindaceae), is a shrub, rarely a small tree, and widely distributes in tropical and subtropical areas of both hemispheres. It is an important afforestation species in the dry and hot valleies in Yunnan. There are many afforestation area of Dodonaea viscosa in the Jinsha River valley and Honghe River valley. Recently, the crude extracts of D. viscosa have been demonstrated molluscicidal activity, herbicidal effect, contact toxicity against Sitophilus oryzae, and antifeedant activities on Plutella xylostella and Pieris rapae by biological and pharmacological experiments. Currently, insecticidal effective ingredients of D. viscosa have not been reported. Nowadays, the development of botanical pesticides has become a hot research field of pesticides. As we all know, an important way of development of new pesticides is extract and isolation new natural products from plants. So, our research focused on the insecticidal effective ingredients to provide information for rational development and utilization of the D. viscosa plant resources. Resources of D. viscosa are abundant in China. Therefore,D. viscosa has broad application prospects if D. viscosa can be developed a new botanical pesticides.In the present study, various separation techniques, such as silica gel column chromatography, macroporous resin column chromatography, preparative TLC and HPLC, were used, combined with modern spectroscopy technology, such as MS, NMR, IR and UV, and biological methods, to isolate and identify the chemical constituents from the aerial parts (branches, leaves and fruits) of D. viscosa, and evaluate the biological activities. The results are as follows:1. Twelve compounds (Ⅰ–Ⅻ) were isolated from the MeOH extract of the aerial parts (branches, leaves and fruits) of D. viscosa. These compounds included two new modified clerodane diterpenoids , methyl dodovisate A (Ⅰ) and methyl dodovisate B (Ⅱ), two new prenylated flavonoids, 5,7,4’-trihydroxy-3’,5’-di(3-methylbut-2-enyl)-3,6-dimethoxyflavone (Ⅹ) and 5,7,4’-trihydroxy-3’-(4-hydroxy-3-methylbutyl)-5’-(3-methylbut-2-enyl)-3,6-dimethoxyflavone (Ⅺ), together with eight known compounds, dodonic acid (Ⅲ), hautriwaic acid (Ⅳ), hautriwaic lactone (Ⅴ), (+)-hardwickiic acid (Ⅵ), 5α-hydroxy-1,2-dehydro-5,10-dihydroprintzianic acid methyl ester (Ⅶ), strictic acid (Ⅷ), dodonolide (Ⅸ), and aliarin (Ⅻ).2. The result of larvicidal activity: CompoundsⅤ,ⅥandⅦshowed weak toxicity to fourth-instar larvae of Culex pipens quinquefasciatus with the LC50 values of 40.7μg/mL, 59.8μg/mL and 122.3μg/mL, respectively;CompoundsⅥandⅦshowed weak toxicity to fourth-instar larvae of Aedes albopictus with the LC50 values of 101.2μg/mL and 135.7μg/mL, respectively.
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