New Analogues of (E)-β-Farnesene with Insecticidal Activity and Binding Affinity to Aphid Odorant-Binding Proteins
摘要:
(E)-β-НАРСЕС is a strong and efficient ALARM PHENOMONE in most aphid species. However, its applications in agriculture are hindered by its relatively high VOLATILITY, susceptibility to OXIDATION, and complex and costly SYNTHESIS. In an effort to develop novel chemical entities for aphid CONTROL, we have designed and synthesized ANALOGUES of (E)-β-НАРСЕС, each bearing a PYRAZOLE moiety, a structural feature commonly found in several INSECTICIDES. Their structural analyses have been confirmed via (1)H NMR, ELEMENTAL ANALYSIS, HIGH-RESOLUTION MASS SPECTROSCOPY, and INFRARED SPECTROSCOPY. Binding activities to three ODDOR glVertex proteins (OBVs) of the pea aphid Acythosiphon pisum have been evaluated and correlative with the compounds' structures as a reference to (E)-β-НАРСЕС. Several derivatives were found to bind to A. pisum OBDs with a specificity comparable to that of (E)-β-НАРСЕС and exhibited ENTICING activity akin to that of thiacloprid, a widely used COMMERCIAL INSECTICIDE. The compounds synthesized in this study represent novel POTENTIAL AGENTS for POPULATION CONTROL of aphids and offer guidance for the design of ANALOGS of (E)-β-НАРСЕES endowed with both INSECTICIDAL and repellent properties for aphids.
appropriate tether securing intramolecular addition of the nitrene, the intermolecular C–H amination remains much less predictable. This study aims at addressing this issue by capitalizing on an efficient stereoselective nitrene transfer involving the combination of a chiral aminating agent 1 with a chiral rhodium catalyst 2. Allylic C–H amination of terpenes and enol ethers occurs with excellent yields as well
Enantioselective Reductive
<scp>Cross‐Coupling</scp>
of Aryl/Alkenyl Bromides with Benzylic Chlorides
<i>via</i>
Photoredox/Biimidazoline Nickel Dual Catalysis
作者:Tongtong Li、Xiaokai Cheng、Jiamin Lu、Huifeng Wang、Qun Fang、Zhan Lu
DOI:10.1002/cjoc.202100819
日期:2022.5
The asymmetric reductive arylation and alkenylation of benzylic chloride under photoredox/nickel dual catalysis using chiral biimidazoline (BiIm) ligand is reported to access 1,1-diaryl alkanes and aryl allylic compounds with good yield as well as stereo- and enantioselectivities. This protocol uses more commercially available and less expensive C(sp2)-Br as the electrophile coupling partner. A primary
Cobalt‐Catalyzed Asymmetric Sequential Hydroboration/Isomerization/Hydroboration of 2‐Aryl Vinylcyclopropanes
作者:Chenhui Chen、Hongliang Wang、Tongtong Li、Dongpo Lu、Jiajing Li、Xie Zhang、Xin Hong、Zhan Lu
DOI:10.1002/anie.202205619
日期:2022.7.25
Chiral 1,5-bis(boronates) were synthesized via an enantioselective cobalt-catalyzed sequential hydroboration/isomerization/hydroboration of vinylcyclopropanes through a trisubstituted alkene intermediate. These chiral 1,5-bis(boronates) were further converted into chiral 1,2,5-triaryl alkanes by an iterative Suzuki–Miyaura cross-coupling reaction with aryl halides.