The title compound 4-（4,6-dimethoxylpyrimidin-2-yl）-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in eth...The title compound 4-（4,6-dimethoxylpyrimidin-2-yl）-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at the room temperature. The structure was characterized by elemental analysis and IR and determined by X-ray diffraction analysis＇ Crystallographic data： C9H12N4O4S, Mr = 272.29, monoclinic, space group C2/m with a = 1.6672（3）, b = 0.66383（12）, c = 1.1617（2） nm, β = 109.275（2）°, V = 1.2136（4） nm^3, Dc = 1.490 g/cm^3,μ = 0.281 mm^-1, F（000） = 568, Z = 4, R1 = 0.0341and wR2 = 0.1042.展开更多
4-（4,6-Dimethoxyl-pyrimidin-2-yl）-3-thiourea carboxylic acid ethyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single ...4-（4,6-Dimethoxyl-pyrimidin-2-yl）-3-thiourea carboxylic acid ethyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at room temperature. The crystal structure was determined by X-ray diffraction analysis. Crystallographic data： C10H14N4O4S, M, = 286.31, monoclinic, space group C2/c with a = 2.5309（3）, b = 0.67682（6）, c = 1.74237（19） nm, β = 114.744（3）°, V= 2.7106（5） nm3, Dc = 1.403 g/cm3, p = 0.225 mm-1, F（000） = 1200, Z= 8, R= 0.0514 and wR= 0.1529.展开更多
Reaction products of 2,4,6-tris(4-phenyl-phenoxy)-1,3,5-triazine derived from 4-phenylphenol cyanate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound w...Reaction products of 2,4,6-tris(4-phenyl-phenoxy)-1,3,5-triazine derived from 4-phenylphenol cyanate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound which were well known as reaction products of cyanate esters and epoxy resins, compounds with hybrid ring structure of cyanurate/isocyanurate were determined. Gibbs free energies of the compound having hybrid ring structure of cyanurate/isocyanurate with two isocyanurate moiety were found to be lower than that of the compound with cyanurate ring structure through calculations. Calculation data supported the existence of hybrid ring structure of cy-anurate/isocyanurate. It was revealed that isomerization from cyanurate to isocyanurate occurs via hybrid ring structure of cyanurate/isocyanurate in the reaction of aryl cyanurate and epoxy.展开更多
We report here a generic,green synthesis of 17 valuable syn-aryl-(2S,3R)-2–chloro-3–hydroxy esters(syn-(2S,3R)-1)in 73%-99%isolated yields along with 6.1:1–83:1 dr and 31%~>99%ee,through dynamic reductive kineti...We report here a generic,green synthesis of 17 valuable syn-aryl-(2S,3R)-2–chloro-3–hydroxy esters(syn-(2S,3R)-1)in 73%-99%isolated yields along with 6.1:1–83:1 dr and 31%~>99%ee,through dynamic reductive kinetic resolution of racemic arylα–chloroβ-keto esters(2)catalyzed by an engineered ketoreductase which was obtained via ep PCR-based directed evolution.The hectogram scale synthesis of syn-(2S,3R)-1b at a substrate concentration of 120 g/L showcased the application potential of the biocatalytic method developed presently.展开更多
A new jatrophane diterpenoid ester （2S, 3S, 4R, 5R, 7S, 8R, 13R, 15R） - 3, 5, 7, 8, 15- pentaacetoxy-9, 14-dioxojatropha-6（17）, 11E-diene was isolated from the whole plant of Euphorbia turczaninowii Kar. ＆ Kit.. ...A new jatrophane diterpenoid ester （2S, 3S, 4R, 5R, 7S, 8R, 13R, 15R） - 3, 5, 7, 8, 15- pentaacetoxy-9, 14-dioxojatropha-6（17）, 11E-diene was isolated from the whole plant of Euphorbia turczaninowii Kar. ＆ Kit.. Its structure was characterized by spectral analysis and confurmed by X-ray crystallographic analysis.展开更多
（S）-2-aminobutyric acid being initial raw material,（S）-2-hydroxybutyric acid methyl ester was synthesized by means of a three step reaction of hydroxylation, salification and esterification. The product had a yiel...（S）-2-aminobutyric acid being initial raw material,（S）-2-hydroxybutyric acid methyl ester was synthesized by means of a three step reaction of hydroxylation, salification and esterification. The product had a yield rate of 60.4%, purity of 99% and ee value higher than 99% by characterization of GC, HPLC and 1H NMR. This synthesis technique has advantages of high purity and ee value, low cost, short reaction time and mild reaction conditions so that it is suitable for production on industrial scale.展开更多
In present literature search, some cyano-containing compounds, which are very rare in plants, from the traditional anticancer herb Tiankuizi were reported. To find more cyano-containing compounds in the important plan...In present literature search, some cyano-containing compounds, which are very rare in plants, from the traditional anticancer herb Tiankuizi were reported. To find more cyano-containing compounds in the important plant Semiaquilegia adoxoides （DC） Makino （Chinese name Tiankuizi）, the isolation of the chemical constituents was investigated for advancing the research. Two new compounds, a new alkaloid, 1,2,3,4-tetrahydro-6-hydroxy-1[（3,4-dihydroxyphenyl）methyl]-7-methoxy-2,2-dimethyl-isoquinolinium, named Semiaquilegine A （1）, and a new ester, 3-（4＇-hydroxyphenyl）-2-propenoic acid （4＂-carboxyl）-phenyl ester （2）, and four cyano-containing compounds, （Z）-6a-（β-D-glucosyloxy）-4a,5a-dihydroxy-2-cyclohexene-△^1,a-acetonitrile （3）, （L0-6α-（β-D-glucosyloxy）-4α-hydroxy-2-cyclohexene-△^1,α-acetonitrile （4）, lithospermoside （5）, ehretioside B （6）, as well as eleven known compounds, were isolated from the roots of Semiaquilegia adoxoides. The structures of new compounds 1 and 2 were elucidated mainly by 1D/2D-NMR techniques. Very unusual cyano-containing compounds 3 and 4 were first isolated from Ranunculaceae family. Hitherto, there were six cyano-containing compounds found in the herb.展开更多
Objective To study the constituents in Melicope pteleifolia.Methods Plant material was isolated with 80% EtOH.Compounds were separated with chromatographic methods and their structures were elucidated on the basis of ...Objective To study the constituents in Melicope pteleifolia.Methods Plant material was isolated with 80% EtOH.Compounds were separated with chromatographic methods and their structures were elucidated on the basis of spectral analysis(EI-MS,1H-NMR,and 13C-NMR) and chemical evidence.Results Five compounds were isolated from petrol ether or ethyl acetate soluble fraction.Their structures were identified as 3,5,3’-trihydroxy-4’-methoxy-7-(3-methylbut-2-enyloxy) flavone(pteleifolosin C,1),3,7-dimethoxyl kaempferol(kamatakenin,2),vanillic acid(3),tricosanoic acid tetradecyl ester(4),and β-sitosterol(5),respectively.Conclusion Compound 1 is a new structure named pteleifolosin C.Compounds 2-4 are isolated from this plant for the first time.展开更多
基金This work was supported by the National Natural Science Foundation of China (20571060) and Education Committee of Shaan Xi Province (05JK294)
文摘The title compound 4-（4,6-dimethoxylpyrimidin-2-yl）-3-thiourea carboxylic acid methyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at the room temperature. The structure was characterized by elemental analysis and IR and determined by X-ray diffraction analysis＇ Crystallographic data： C9H12N4O4S, Mr = 272.29, monoclinic, space group C2/m with a = 1.6672（3）, b = 0.66383（12）, c = 1.1617（2） nm, β = 109.275（2）°, V = 1.2136（4） nm^3, Dc = 1.490 g/cm^3,μ = 0.281 mm^-1, F（000） = 568, Z = 4, R1 = 0.0341and wR2 = 0.1042.
基金supported by the National Natural Science Foundation of China (20571060)Natural Science Foundation of Shaanxi Province (2007B08)Education Committee of Shaanxi Province (05JK294)
文摘4-（4,6-Dimethoxyl-pyrimidin-2-yl）-3-thiourea carboxylic acid ethyl ester was synthesized by the reaction of 2-amino-4,6-dimethoxyl pyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray measurement were obtained by recrystallization with the solvent of dimethyl formamide at room temperature. The crystal structure was determined by X-ray diffraction analysis. Crystallographic data： C10H14N4O4S, M, = 286.31, monoclinic, space group C2/c with a = 2.5309（3）, b = 0.67682（6）, c = 1.74237（19） nm, β = 114.744（3）°, V= 2.7106（5） nm3, Dc = 1.403 g/cm3, p = 0.225 mm-1, F（000） = 1200, Z= 8, R= 0.0514 and wR= 0.1529.
文摘Reaction products of 2,4,6-tris(4-phenyl-phenoxy)-1,3,5-triazine derived from 4-phenylphenol cyanate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound which were well known as reaction products of cyanate esters and epoxy resins, compounds with hybrid ring structure of cyanurate/isocyanurate were determined. Gibbs free energies of the compound having hybrid ring structure of cyanurate/isocyanurate with two isocyanurate moiety were found to be lower than that of the compound with cyanurate ring structure through calculations. Calculation data supported the existence of hybrid ring structure of cy-anurate/isocyanurate. It was revealed that isomerization from cyanurate to isocyanurate occurs via hybrid ring structure of cyanurate/isocyanurate in the reaction of aryl cyanurate and epoxy.
基金The National Key Research and Development Program of China(Nos.2021YFA0911400 and 2021YFF0600704)the National Natural Science Foundation of China(Nos.22071033 and 21801047)are acknowledged for the financial supports。
文摘We report here a generic,green synthesis of 17 valuable syn-aryl-(2S,3R)-2–chloro-3–hydroxy esters(syn-(2S,3R)-1)in 73%-99%isolated yields along with 6.1:1–83:1 dr and 31%~>99%ee,through dynamic reductive kinetic resolution of racemic arylα–chloroβ-keto esters(2)catalyzed by an engineered ketoreductase which was obtained via ep PCR-based directed evolution.The hectogram scale synthesis of syn-(2S,3R)-1b at a substrate concentration of 120 g/L showcased the application potential of the biocatalytic method developed presently.
文摘A new jatrophane diterpenoid ester （2S, 3S, 4R, 5R, 7S, 8R, 13R, 15R） - 3, 5, 7, 8, 15- pentaacetoxy-9, 14-dioxojatropha-6（17）, 11E-diene was isolated from the whole plant of Euphorbia turczaninowii Kar. ＆ Kit.. Its structure was characterized by spectral analysis and confurmed by X-ray crystallographic analysis.
文摘（S）-2-aminobutyric acid being initial raw material,（S）-2-hydroxybutyric acid methyl ester was synthesized by means of a three step reaction of hydroxylation, salification and esterification. The product had a yield rate of 60.4%, purity of 99% and ee value higher than 99% by characterization of GC, HPLC and 1H NMR. This synthesis technique has advantages of high purity and ee value, low cost, short reaction time and mild reaction conditions so that it is suitable for production on industrial scale.
文摘In present literature search, some cyano-containing compounds, which are very rare in plants, from the traditional anticancer herb Tiankuizi were reported. To find more cyano-containing compounds in the important plant Semiaquilegia adoxoides （DC） Makino （Chinese name Tiankuizi）, the isolation of the chemical constituents was investigated for advancing the research. Two new compounds, a new alkaloid, 1,2,3,4-tetrahydro-6-hydroxy-1[（3,4-dihydroxyphenyl）methyl]-7-methoxy-2,2-dimethyl-isoquinolinium, named Semiaquilegine A （1）, and a new ester, 3-（4＇-hydroxyphenyl）-2-propenoic acid （4＂-carboxyl）-phenyl ester （2）, and four cyano-containing compounds, （Z）-6a-（β-D-glucosyloxy）-4a,5a-dihydroxy-2-cyclohexene-△^1,a-acetonitrile （3）, （L0-6α-（β-D-glucosyloxy）-4α-hydroxy-2-cyclohexene-△^1,α-acetonitrile （4）, lithospermoside （5）, ehretioside B （6）, as well as eleven known compounds, were isolated from the roots of Semiaquilegia adoxoides. The structures of new compounds 1 and 2 were elucidated mainly by 1D/2D-NMR techniques. Very unusual cyano-containing compounds 3 and 4 were first isolated from Ranunculaceae family. Hitherto, there were six cyano-containing compounds found in the herb.
文摘Objective To study the constituents in Melicope pteleifolia.Methods Plant material was isolated with 80% EtOH.Compounds were separated with chromatographic methods and their structures were elucidated on the basis of spectral analysis(EI-MS,1H-NMR,and 13C-NMR) and chemical evidence.Results Five compounds were isolated from petrol ether or ethyl acetate soluble fraction.Their structures were identified as 3,5,3’-trihydroxy-4’-methoxy-7-(3-methylbut-2-enyloxy) flavone(pteleifolosin C,1),3,7-dimethoxyl kaempferol(kamatakenin,2),vanillic acid(3),tricosanoic acid tetradecyl ester(4),and β-sitosterol(5),respectively.Conclusion Compound 1 is a new structure named pteleifolosin C.Compounds 2-4 are isolated from this plant for the first time.
