- Synthesis and stereostructure-activity relationship of novel pyrethroids possessing two asymmetric centers on a cyclopropane ring
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2-Methylcyclopropane pyrethroid insecticides bearing chiral cyanohydrin esters or chiral ethers and two asymmetric centers on the cyclopropane ring, were synthesized. These compounds were designed using a “reverse connection approach” between the isopropyl group in Fenvalerate, and between two dimethyl groups in an Etofenprox analogue (the methyl, ethyl form), respectively. These syntheses were achieved by accessible ring opening reactions of commercially available (±)-, (R)-, and (S)-propylene oxides using 4-chlorobenzyl cyanide anion as the crucial step, giving good overall yield of the product with >98% ee. The insecticidal activity against the common mosquito (Culex pipiens pallens) was assessed for pairs of achiral diastereomeric (1R*,2S*)-, (1R*,2R*)-cyanohydrin esters, and (1R*,2S*)-, (1R*,2R*)-ethers; only the (1R*,2R*)-ether was significantly effective. For the enantiomeric (1S,2S)-ether and (1R,2R)-ether, the activity was clearly centered on the (1R,2R)-ether. The present stereostructure?activity relationship revealed that (i) cyanohydrin esters derived from fenvalerate were unexpectedly inactive, whereas ethers derived from etofenprox were active, and (ii) apparent chiral discrimination between the (1S,2S)-ether and the (1R,2R)-ether was observed. During the present synthetic study, we performed alternative convergent syntheses of Etofenprox and novel 4-EtO-type (1S,2S)- and (1R,2R)-pyrethroids from the corresponding parent 4-Cl-type pyrethroids, by utilizing a recently-developed hydroxylation cross-coupling reaction.
- Taniguchi, Takashi,Taketomo, Yasuaki,Moriyama, Mizuki,Matsuo, Noritada,Tanabe, Yoo
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supporting information
(2019/03/26)
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- Br?nsted Acid-Catalyzed Intramolecular Hydroarylation of β-Benzylstyrenes
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Using triphenylmethylium tetrakis(pentafluorophenyl)borate as a convenient Br?nsted acid precatalyst, β-(α,α-dimethylbenzyl)styrenes are shown to cyclize efficiently to afford a variety of new indanes that possess a benzylic quaternary center. The geminal dimethyl-containing quaternary center is proposed to be necessary to arm the substrate for cyclization through steric biasing.
- Cai, Xiao,Keshavarz, Amir,Omaque, Justin D.,Stokes, Benjamin J.
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supporting information
p. 2626 - 2629
(2017/05/24)
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- AKT PROTEIN KINASE INHIBITORS
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The present invention provides compounds, including resolved enantiomers, diastereomers, solvates and pharmaceutically acceptable salts thereof, comprising the Formula: A-L-CR where CR is a cyclical core group, L is a linking group and A is as defined herein. Also provided are methods of using the compounds of this invention as AKT protein kinase inhibitors and for the treatment of hyperproliferative diseases such as cancer.
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Page/Page column 129-130
(2008/06/13)
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- 5[W(substituted aryl)alkenylene and alkynylene]-2,4-diaminopyrimidines as pesticides
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5-Substituted-2,4-diaminopyrimidines, and agriculturally acceptable salts thereof, when present in insecticidally or acaricidally effective amounts, and with a suitable agricultural carrier, are useful as active ingredients in novel insecticidal and acaricidal compositions. These pyrimidines may be represented by the following formula: STR1 wherein Ar is STR2 and wherein U is an alkenylene or alkynylene moiety, and R, R1, R2, R3, R4, V, W, X, Y, Z and n are as defined herein; also disclosed and claimed are novel intermediates thereof.
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- 2-aryl-ethyl ether derivatives and insecticidal and acaricidal agents containing said derivatives
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The present invention relates to 2-arylethyl ether or thioether derivatives represented by the following general formula [I]: STR1 wherein Ar stands for an aryl group, R1 stands for straight or branched chain alkyl group of 1 to 6 carbons, R2 stands for a hydrogen atom, or a methyl or ethyl group, R3 stands for a halogen atom, or a methyl or methoxyl group, R4 stands for a hydrogen or halogen atom, or a lower alkyl or lower alkoxy group, and n is an integer of 1 or 2 with the proviso that when n is 2, the groups R4 may be the same or different, and Y stands for an oxygen or sulfur atom, and also to processes for the preparation of these ethers or thioethers and a use of these ethers or thioethers. These compounds of the present invention have excellent insecticidal and acaricidal activities while the toxicity of these compounds are very low.
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- 2-Arylpropyl ether or thioether derivatives and insecticidal and acaricidal agents containing said derivatives
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The present invention relates to 2-arylpropyl ether or thioether derivatives represented by the following general formula [I]: STR1 wherein Ar stands for an aryl group, R stands for a methyl or ethyl group, Y stands for an oxygen or sulfur atom, and B stands for a group represented by the following formula [II]: STR2 or the following general formula [III]: STR3 wherein Z stands for an oxygen or sulfur atom or a carbonyl or methylene group, R1 stands for a hydrogen or halogen atom or a lower alkyl group or a lower alkoxy group, and n is an integer of from 1 to 5 with the proviso that when n is 2 or more, the groups R1 may be the same or different, and also to processes for the preparation or these ethers of thioethers and a use of these ethers or thioethers. These compounds of the present invention have excellent insecticidal and acaricidal activities while the toxicity of these compounds are very low.
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