Main observation and conclusion A pair of new enantiomeric compounds,(R)/(S)-1,3,5-benzene-triyl-2,2',2”-tris(4,5-dihydrothiazole-4-carboxylic acid)(H3LRRR and H3LSSS)are synthesized in one step synthetic route w...Main observation and conclusion A pair of new enantiomeric compounds,(R)/(S)-1,3,5-benzene-triyl-2,2',2”-tris(4,5-dihydrothiazole-4-carboxylic acid)(H3LRRR and H3LSSS)are synthesized in one step synthetic route with high yield.Instant photochromism has been investigated to elaborate the photocatalytic decarboxylation of the dihydrothiazole derivative by electron paramagnetic resonance spectroscopy(EPR),photoluminescence(PL),FT-IR,high resolution mass spectra,X-ray photoelectron spectroscopy and UV-Vis spectroscopic techniques.The results indicate that the photochromic transformation is originated from the formation of the radical during the photocatalytic decarboxylation of the 4,5-dihydrothiazole-4-carboxylic acid units.展开更多
A series of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety were synthesized and characterized on the basis of NMR and elemental analysis(EA). The crystal structure of(R)-N-(...A series of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety were synthesized and characterized on the basis of NMR and elemental analysis(EA). The crystal structure of(R)-N-(2-methyl-1-(methylthio)propan-2-yl)-2-(4-nitrophenyl)-4,5-dihydrothiazole-4-carboxamide(13 d) was determined to show R configuration. The bioasssy results indicated that most title compounds displayed good and broad spectrum antifungal activities against several phytopathogenic fungi. The structure activity relationships were discussed. Based on the antifungal activity of title compounds against Phytophthora capsici, a CoMSIA calculation was performed to establish a 3 D-QSAR model, which revealed that electrostatic and hydrophobic fields were the two most significant factors for antifungal activity. According to the established 3D-QSAR model, structure optimization was carried out to find(R)-N-((R)-1-(methylthio)propan-2-yl)-2-(p-tolyl)-4,5-dihydrothiazole-4-carboxamide(15 h)with excellent activity against Phytophthora capsici, thus emerging as a new lead compound for novel antiphytopathogenic fungus agent development.展开更多
The title compound diethyl 2-（3,4-dichloroisothiazol-5-yl）-4-（trifluoromethyl）-4,5- dihydrothiazol-4-yl-3-methylbenzoate （C15H9C12F3N202S2, Mr = 441.26） was prepared from methyl 3,4-dichloroisothiazole-5-carboxy...The title compound diethyl 2-（3,4-dichloroisothiazol-5-yl）-4-（trifluoromethyl）-4,5- dihydrothiazol-4-yl-3-methylbenzoate （C15H9C12F3N202S2, Mr = 441.26） was prepared from methyl 3,4-dichloroisothiazole-5-carboxylate as the starting material by four steps of reaction. Its structure was characterized by IR, 1H-NMR, 13C-NMR, EA and single-crystal X-ray diffraction. The crystal of the title compound belongs to the monoclinic system, space group P2dc with a = 8.8437（18）, b = 16.128（3）, c = 12.305（3） A, β = 91.68（3）°, V= 1754.4（6） A3, Z = 4, Dc = 1.671 g/cm3,μ（MoKa） = 0,71073 mm^-1, F（000） = 888, R = 0.0384 and wR = 0.0778. Weak π-π interactions occur between the isothiazole rings and phenyl rings of adjacent molecules to form a one-dimensional chain and stabilize the crystal structure. Bioassay indicates that the title compound has good activity against the fungi and TMV tested.展开更多
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
A series of novel 2,3-dihydro-2-phenylsulfonylhydrazono-3-（2＇,3＇,4＇,6＇-tetra-O-acetyl-β-D-glucopyranosyl）thiazoles were designed and synthesized via the reaction of thiosemicarbazide with chloroaldehyde. Their ...A series of novel 2,3-dihydro-2-phenylsulfonylhydrazono-3-（2＇,3＇,4＇,6＇-tetra-O-acetyl-β-D-glucopyranosyl）thiazoles were designed and synthesized via the reaction of thiosemicarbazide with chloroaldehyde. Their chemical structures were characterized by ^1H and ^13C NMR spectroscopy and elemental analysis. The bioassay results indicate that some of these compounds exhibit moderate fungicidal and herbicidal activities.展开更多
基金sponsored by the Natural Science Foundation of Shanghai(Grant No.19ZR1424900).
文摘Main observation and conclusion A pair of new enantiomeric compounds,(R)/(S)-1,3,5-benzene-triyl-2,2',2”-tris(4,5-dihydrothiazole-4-carboxylic acid)(H3LRRR and H3LSSS)are synthesized in one step synthetic route with high yield.Instant photochromism has been investigated to elaborate the photocatalytic decarboxylation of the dihydrothiazole derivative by electron paramagnetic resonance spectroscopy(EPR),photoluminescence(PL),FT-IR,high resolution mass spectra,X-ray photoelectron spectroscopy and UV-Vis spectroscopic techniques.The results indicate that the photochromic transformation is originated from the formation of the radical during the photocatalytic decarboxylation of the 4,5-dihydrothiazole-4-carboxylic acid units.
基金financially supported by the Scientific Project of Tianjin Municipal Education Commission(No. 2018KJ008)Tianjin Natural Science Foundation(No. 16JCYBJC29400)
文摘A series of(R)-2-phenyl-4,5-dihydrothiazole-4-carboxamide derivatives containing a sulfur ether moiety were synthesized and characterized on the basis of NMR and elemental analysis(EA). The crystal structure of(R)-N-(2-methyl-1-(methylthio)propan-2-yl)-2-(4-nitrophenyl)-4,5-dihydrothiazole-4-carboxamide(13 d) was determined to show R configuration. The bioasssy results indicated that most title compounds displayed good and broad spectrum antifungal activities against several phytopathogenic fungi. The structure activity relationships were discussed. Based on the antifungal activity of title compounds against Phytophthora capsici, a CoMSIA calculation was performed to establish a 3 D-QSAR model, which revealed that electrostatic and hydrophobic fields were the two most significant factors for antifungal activity. According to the established 3D-QSAR model, structure optimization was carried out to find(R)-N-((R)-1-(methylthio)propan-2-yl)-2-(p-tolyl)-4,5-dihydrothiazole-4-carboxamide(15 h)with excellent activity against Phytophthora capsici, thus emerging as a new lead compound for novel antiphytopathogenic fungus agent development.
基金funded in part by the Tianjin Natural Science Foundation(No.14JCYBJC20400)the"111"Project of Ministry of Education of China(No.B06005)NFFTBS(No.J1103306)
文摘The title compound diethyl 2-（3,4-dichloroisothiazol-5-yl）-4-（trifluoromethyl）-4,5- dihydrothiazol-4-yl-3-methylbenzoate （C15H9C12F3N202S2, Mr = 441.26） was prepared from methyl 3,4-dichloroisothiazole-5-carboxylate as the starting material by four steps of reaction. Its structure was characterized by IR, 1H-NMR, 13C-NMR, EA and single-crystal X-ray diffraction. The crystal of the title compound belongs to the monoclinic system, space group P2dc with a = 8.8437（18）, b = 16.128（3）, c = 12.305（3） A, β = 91.68（3）°, V= 1754.4（6） A3, Z = 4, Dc = 1.671 g/cm3,μ（MoKa） = 0,71073 mm^-1, F（000） = 888, R = 0.0384 and wR = 0.0778. Weak π-π interactions occur between the isothiazole rings and phenyl rings of adjacent molecules to form a one-dimensional chain and stabilize the crystal structure. Bioassay indicates that the title compound has good activity against the fungi and TMV tested.
基金We gratefully acknowledge the financial support of this work by the ＂111＂ Project of Ministry of Education of China （No. B06005） and the Natural Science Foundation of China （No. 31370039）.
文摘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.
基金Supported by the National Basic Research Program of China(No.2003CB114406)the Science and Technology Innova-tion Foundation of Nankai University, China.
文摘A series of novel 2,3-dihydro-2-phenylsulfonylhydrazono-3-（2＇,3＇,4＇,6＇-tetra-O-acetyl-β-D-glucopyranosyl）thiazoles were designed and synthesized via the reaction of thiosemicarbazide with chloroaldehyde. Their chemical structures were characterized by ^1H and ^13C NMR spectroscopy and elemental analysis. The bioassay results indicate that some of these compounds exhibit moderate fungicidal and herbicidal activities.
