Toshihiko Yano

THE ABSOLUTE STRUCTURE AND ACTIVITY RELATIONSHIPS OF MAJOR SECONDARY ALCOHOLS OF PYRETHROID INSECTICIDES

ABSTRACT Optically active forms of various χ-ethynyl pyrethroid alcohol moieties were newly prepared for determination of their absolute configurations, and the toxicity ratios of the respective (S)-alcohol ester to the (R)-ester to housefly were assessed. As for the acyclic χ-ethynyl alcohol esters, the toxicity ratios were generally high and consistent over available examples. Whereas, the ratios were essentially dependent on both the species and position of a substituent on the benzene ring regarding the χ-ethynylbenzyl analogs. The essential stereochemical requirements for the active ethynyl alcohols were discussed in comparison with other major secondary alcohols as represented by (S)-allethrolone and (S)-χ-cyano-3-phenoxybenzyl alcohol.

Insecticidal Activity of Pyrethroids Containing a Heterocycle against Musca domestica and Their Structure-Activity Relationship

種々のヘテロ環をアルコール成分に有するピレスロイドを合成し, イエバエに対する殺虫活性を測定した. その結果, 活性は, 導入されるヘテロ環の種類に著しく影響を受けることが明らかとなった. これらピレスロイドの安定コンフォメーションをMNDO法を用いて計算し, 2-ベンジル-4-フリルメチル2,2-ジメチル-3-(2,2-ジクロロビニル) シクロプロパンカルボキシレートを対照分子として立体類似性 (RMS値) を算出した. RMS値および逆相液体クロマトグラフィーを用いて測定したlogk′値は殺虫活性と相関性を示し, ピレスロイドの殺虫活性における立体形状と疎水性の重要性が示唆された.