Synthesis And Insecticidal Activity Of The Ether Analogues Of β-dihydroagarofuran

In order to make full use of Celastrus angulatus Max. and study the relationshipbetween structure and insecticidal activity of β-dihydroagarofuran compounds1β,2β,4α,6α,8β,9α,12-hepthydroxy-β-dihydroagarofuran polyol, has been isolated from the h-ydrolysate extract of the root bark of Celastrus angulatus Max..Using the purified, ex-tracted compound as crude material, we investigated the structure dependence of insec-ticidalactivity of its derivatives. Reacting the crude material with methylsulfonyl chlori-de,followed by lithium aluminum hydride,1β,4α,6α9α-tetrahydroxy-2β,12-ether-β-dih-ydroagarof-uran (S) was isolatedand chosen as a starting material for the synthesis ofvarious β-dihydroagarofuran compounds.1β,4α,6α,9α-tetrahydroxy-2β,12-ether-β-dihydroagarofuran and senven ether der-ivatives were synthesized; Furthermore, twelve ether derivatives of6α-p-fluorobenzylox-y-1β,4α,9α-trihydroxy-2β,12-ether-β-dihydroagarofuran,1β,4α,6α-dihydro-xy-1β,9α-cyclic sulphate-2β,12-ether-β-dihydroagarofuran and6α-carbonyl-1β,4α,9α-t-rihydroxy-2β,12-ether-β-dihydroagarofuran as well as eight derivatives of6α-Allyloxy-1β,4α,9α-trihydroxy-2β,12-ether-β-dihydroagarofuran,6α-butyloxy-1β,4α,9α-trihydroxy-2β,12-ether-β-dihydroagarofuran were synthesized.All structures information of the compounds were obtained by NMR spectroscopy.The insecticidal activities of the derivatives were evaluated against third-instar larvaeof Mythimna separata.The results showed that the insecticidal mechanism of the synth-esized compounds are similar to celangulin Ⅴ,1α-p-fluorobenzyloxy is a pivotal grou-p to insecticidal activity, the group linked at C-1should be small as well as the pers-sad at C-9.The structure dependence of biological activity will guide structural modifications tocelangulin for applications.