Total Syntheses of All Six Chiral Natural Pyrethrins: Accurate Determination of the Physical Properties, Their Insecticidal Activities, and Evaluation of Synthetic Methods
作者:Momoyo Kawamoto、Mizuki Moriyama、Yuichiro Ashida、Noritada Matsuo、Yoo Tanabe
DOI:10.1021/acs.joc.9b02767
日期:2020.3.6
I were synthesized. Three alternative syntheses of (±)-jasmololone were investigated (methods utilizing Piancatelli rearrangement, furan transformation, and 1-nitropropene transformation). Insecticidal activity assay (KD50 and IC50) against the common mosquito (Culex pipiens pallens) revealed that (i) pyrethrin I > pyrethrin II, (ii) pyrethrin I (II) > cinerin I (II) ≫ jasmolin I (II), and (iii) "natural"
菊花(解热丝)花中所含的全部六个杀虫性天然除虫菊酯(三个除虫菊酯I和三个除虫菊酯II化合物)的手性总合成。合成了三种常见的醇成分[(S)-香气酮,(S)-茉莉香酮和(S)-吡咯烷酮]:(i)使用可用的(S)-4-羟基-3-甲基的直接Sonogashira型交叉偶联剂(S)-苯环戊酮(总产率52%,ee 98%)和(S)-吡咯烷酮(总产率54%) 98%ee)和(ii)(S)-茉莉醇酮的传统脱羧-醛醇缩合和脂肪酶催化的光学拆分(总收率16%,ee为96%)。制备了两个反酸链段[(1R,3R)-菊酸(A)和(1R,3R)-第二菊酸前体(B)]:(i)C(1)-(±)-菊苣酸酯的差向异构化,并使用(S)-萘乙胺进行光学拆分,得到A(96%ee),以及(ii)A简化为B的衍生化(96%ee)。使用易得的酯化试剂(TsCl / N-甲基咪唑)成功合成了全部六个除虫菊酯(cinerin I / II,茉莉素I