SYNTHESIS AND INSECTICIDAL ACTIVITY OF SOME PYRETHROID-LIKE COMPOUNDS INCLUDING ONES LACKING CYCLOPROPANE OR ESTER GROUPINGS

Twelve new pyrethroidlike compounds were synthesized. eight of which have insecticidal characteristics similar to that of pyrethrum. The new compounds structurally resemble allethrin or 5-benzyl-3-furylmethyl chrysanthemumate and they include carboxylic acid esters, carbamic acid esters, carboxamides, and ketones. Replacement of the ester oxygen bridge by a methylene group, to form a ketone, or an amino group, to form a carboxamide, does not alter the type of biological activity but greatly reduces the potency. Substitution of the 2,2,3,3-tetramethylcyclopropyl moiety for the 2,2-dimethyl-3-isobutenylcyclopropyl moiety does not greatly alter the insecticidal activity, in any one of the ester, amide, and ketone series. Pyrethroidlike activity, although of low magnitude, persists on replacing the tetramethylcyclopropyl group by a tetramethylaziridino group or, even by a diisopropylamino group. There is limited evidence that the carbonyl group adjacent to the cyclopropane ring, or an activity-retaining replacement of the ring, is a requirement for insecticidal activity, and clearly, the ester linkage is not an essential feature for activity. © 1969, American Chemical Society. All rights reserved.