Effect on Insecticidal Activity of Substituents at the 1,4-Benzodioxanyl Moiety of Haedoxan

The haedoxan analog, (±)-2-(2,6-dimethoxyphenoxy)-1-hydroxy-6-(6-methoxy-1,4-benzodioxan-7-yl)-3,7-dioxabicyclo[3.3.0]octane, and its congeners with 2-alkoxymethyl, 2-hydroxymethyl, 2-chloro-methyl and 3-(3,4-methylenedioxyphenyl) substituents on the 1,4-benzodioxanyl group were synthesized from 6-methoxy-1,4-benzodioxan-7-carbaldehyde and its (±)-2-and 3-substituted derivatives, respectively. Some analogs were considerably insecticidal, although much less active than natural haedoxan A. The assay results suggest that 2,3-disubstitution on the 1,4-benzodioxanyl group was necessary to intensify the insecticidal activity.