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Synthesis of (R)(E)-3,7-Dimethyl-2-octene-1,8-dioic Acid, a Copulation Released Pheromone Component of Azuki Bean Weevil
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作者 YU Guang-ao HUANG Jin-xia +2 位作者 HOU Jun-li Li Yan XU Zhang-huang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第4期397-399,共3页
Started from 5-hydroxy-2-pentanone, (R)(E)-3,7-dimethyl-2-octene-1,8-dioic acid, callosobruchusic acid, was synthesized via five steps with D-(-)-camphor sultam as the chiral auxiliary. It was of good optical purity a... Started from 5-hydroxy-2-pentanone, (R)(E)-3,7-dimethyl-2-octene-1,8-dioic acid, callosobruchusic acid, was synthesized via five steps with D-(-)-camphor sultam as the chiral auxiliary. It was of good optical purity and yield. 展开更多
关键词 Synthesis (r)(E)-3 7-Dimethyl-2-octene-1 8-dioic acid Copulation released pheromone
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Crystal Structure and Biological Activities of (R)-N′-[2-(4-Methoxy-6-chloro)-pyrimidinyl]-N-[3-methyl-2-(4-chlorophenyl)butyryl]-urea
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作者 LI Jing-Zhi XUE Si-Jia LIU Guo-Hua 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第8期903-908,共6页
The title compound (R)-N′-[2-(4-methoxy-6-chloro)-pyrimidyl]-N-[3-methyl-2-(4- chlorophenyl)butyryl]-urea has been synthesized, and its crystal structure and biological behaviors were studied. Crystallographic ... The title compound (R)-N′-[2-(4-methoxy-6-chloro)-pyrimidyl]-N-[3-methyl-2-(4- chlorophenyl)butyryl]-urea has been synthesized, and its crystal structure and biological behaviors were studied. Crystallographic data: C17H18C12N4O3, Mr = 397.25, monoclinic, space group P21/c, a = 12.331(2), b = 14.025(3), c = 23.085(5) A, β = 99.607(4)°, Z = 8, V = 3936.2(13) A3, Dc = 1.341 g/cm^3, F(000) = 1648, R = 0.0718, wR = 0.1585 and/t(MoKα) = 0.353 mm^-1. The preliminary biological tests showed that the title compound has definite insecticidal and fungicidal activities. 展开更多
关键词 crystal structure biological activity (r)-3-methyl-2-(4-chlorophenyl)butyric acid 2-amino-6-chloro-4-methoxy-pyrimidine
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Enantioselective esterification of(R,S)-2-(4-methylphenyl)propionic acid via Novozym 435:Optimization and application
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作者 Xin Yuan LujunWang +2 位作者 Panliang Zhang Weifeng Xu Kewen Tang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第7期1816-1823,共8页
This paper reports on the resolution of(R,S)-2-(4-methylphenyl)propionic acid(MPPA)enantiomers by enzymatic esterification in organic solvent.Novozym 435(CALB)has the best catalytic performance compared with other lip... This paper reports on the resolution of(R,S)-2-(4-methylphenyl)propionic acid(MPPA)enantiomers by enzymatic esterification in organic solvent.Novozym 435(CALB)has the best catalytic performance compared with other lipases.Of the alcohols screened,n-hexanol is the best acyl acceptor and gives the highest enzyme activity and enantioselectivity in n-hexane.Response surface methodology(RSM)was used to evaluate the influence of the factors,such as temperature,enzyme amount,substrate concentration and reaction time on the substrate conversion(c)and enantiomeric excess(ee).The correlation coefficient R2 for enantiomeric excess and the conversion are 0.9827 and 0.9910,respectively,indicating that can accurately predict the experimental results.By simulation and optimization,the optimal conditions were obtained,involving 600 mmol·L^-1 MPPA concentration(0.60 mmol),850 mmol·L^-1 hexanol concentration(0.85 mmol),58 mg enzyme amount,75℃temperature and 4.5 h reaction time,respectively.Under the optimized conditions,the experimental values of conversion and enantiomeric excess were 89.34%and 97.84%,respectively,which are in good agreement with the model predictions. 展开更多
关键词 (r S)-2-(4-Methylphenyl)propionic acid Novozym 435 ESTErIFICATION kinetic resolution response surface methodology
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Design, Synthesis, Antifungal Activities and SARs of (R)-2-Aryl-4,5-dihydrothiazole-4-carboxylic Acid Derivatives 被引量:2
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作者 Jingbo Liu Yuxin Li Youwei Chen Xuewen Hua Yingying Wan Wei Wei Haibin Song Shujing Yu Xiao Zhang Zhengming Li 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2015年第11期1269-1275,共7页
Based on the structure of natural product 2-aryl-4,5-dihydrothiazole-4-carboxylic acid, a series of novel (R)-2-aryl-4,5-dihydrothiazole-4-carboxylic acid derivatives were designed and synthesized. Their structures ... Based on the structure of natural product 2-aryl-4,5-dihydrothiazole-4-carboxylic acid, a series of novel (R)-2-aryl-4,5-dihydrothiazole-4-carboxylic acid derivatives were designed and synthesized. Their structures were characterized by ^1H NMR, ^13C NMR and HRMS. The single crystal structure of compound 9b was determined by X-ray diffraction analysis. The antifungal activities were evaluated for the first time. The bioassay results indicated that most compounds exhibited moderate to good antifungal activities. The antifungal activities of compound 13a (against Cercospora arachidicola Hori), 13d (against Alternaria solani), and 16e (against Cercospora arachidieola Hori) were 61.9%, 67.3% and 61.9%, respectively, which are higher than those of the commercial fungicides chlorothalonil and carbendazim. Moreover, compound 13d exhibited excellent antifungal activities against 7 kinds of the fungi tested (66.7%, 77.3%, 63.0%, 87.9%, 70.0%, 70.0% and 80.0% at 50 μg/mL). Therefore, 13d can be used as a new lead structure for the development of antifungal agents. 展开更多
关键词 (r)-2-aryl-4 5-dihydrothiazole-4-carboxylic acid SYNTHESIS antifungal activity structure-activity relationship
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Resolution of racemic R.S-α-arylethylamine by a new resolving agent (R)thiazolidine-2-thione-4-carboxylic acid 被引量:1
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作者 李叶芝 郭纯孝 +1 位作者 卜卫明 黄化民 《Science China Chemistry》 SCIE EI CAS 1998年第4期361-370,共10页
Racemic R.S α arylethylamine was resolved by R(-)thiazolidine 2 thione 4 carboxylic acid, a new resolving agent abbreviated as , by which R(-)TTCA·S(-) arylethylamine salts 2a - 2e, 20 D= -47.24°\-64.... Racemic R.S α arylethylamine was resolved by R(-)thiazolidine 2 thione 4 carboxylic acid, a new resolving agent abbreviated as , by which R(-)TTCA·S(-) arylethylamine salts 2a - 2e, 20 D= -47.24°\-64.40° and optically active R(+) α arylethylamines 3a - 3e , 74.54%\94.45% e.e., were obtained. Optically active S(-) α arylethylamines 4a - 4e , 72.84%\90.36% e.e., were obtained by the decomposition of 2a - 2e in basic solutions. The influence of substitutive group of the benzene ring on the basicity of the amino group was studied by semiempirical PM3 method. The structures of the R(-)TTCA·S(-) α phenylethylamine salt (2a(R S) configuration) and R(-)TTCA·R(+) α phenylethylamine salt (2a′(R R) configuration) have been established by means of X ray diffraction. They crystallize in a monoclinic system. Space group is P 2 l. The cell constants of 2a(R S) configuration were obtained as follows: a =1.387 8(2), b =0.664 05(10), c =1.580 0(2) nm; β =90 844(10)°, Z=4 ; those obtained for 2a′(R R) configuration were a= 1.080 6(2), b =0.584 80(12), c = 1.218 8(2) nm, β =110.38(3)°, V =0.722 0 nm 3, Z =2. There are intermolecular hydrogen bonds in the crystals of the two kinds of configurations of the amine salt. The hydrogen bond number in the unit cell of R(-)TTCA·S(-) α phenylethylamine salt is twice as much as that of R(-)TTCA·R(+) α phenylethylamine salt. 展开更多
关键词 new resolving AGENT r(-) THIAZOLIDINE 2 THIONE 4 carboxylic acid r(+) α arylethylamine S(-) α arylethylamine rESOLUTION electronic STrUCTUrE crystal STrUCTUrE intermolecular hydrogen bond.
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Crystal Structure of Isoquinoline Derivatives
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作者 罗梅 张家海 +3 位作者 周仕明 孙杰 尹浩 胡克 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1672-1674,共3页
The chiral compound 5H-imidazol[2,3-b]isoquinoline-l-ethanol-5-one-1,2, 3, 10b-tetrahydro- β(S)-phenyl-3(S)-phenyl was synthesized from the direct condensation of 2- cyanophenyacetonitrile with optically active ... The chiral compound 5H-imidazol[2,3-b]isoquinoline-l-ethanol-5-one-1,2, 3, 10b-tetrahydro- β(S)-phenyl-3(S)-phenyl was synthesized from the direct condensation of 2- cyanophenyacetonitrile with optically active (S)-(+)-2-phenylglycinol in chlorobenzene under dry, anaerobic conditions. ZnCl2 was used as a Lewis acid catalyst in this reaction, and the structure of this compound was determined by X-ray diffraction, NMR, MS and IR. Crystal data of the title compound: C25H22N2O2, Mr = 382.45, P 21 21 21, a = 5.341(5), b = 16.735(5), c = 22.129(5) A, γ = 90°, V = 1978(2)A^3, Z = 4, Dc = 1.284 g/cm^3, the final R = 0.0321 for 2269 observed reflections with I 〉 2 σ(I) and Rw = 0.0771 for all data. 展开更多
关键词 5H-imidazol[2 3-b]isoquinoline-l-ethanol-5-one-1 2 3 10b-tetrahydro- β(S)-phenyl-3(S)-phenyl (r)--)-2-phenylglyeinol Lewis acid eatalyst
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