Toluene-2,4-bisurea (TBU) is an important intermediate for urea route to dimethyl toluene-2,4-dicarbamate and the study on TBU synthesis via the reaction of 2,4-toluene diamine (TDA) and urea is of great significance....Toluene-2,4-bisurea (TBU) is an important intermediate for urea route to dimethyl toluene-2,4-dicarbamate and the study on TBU synthesis via the reaction of 2,4-toluene diamine (TDA) and urea is of great significance. Firstly, thermodynamic analysis shows that the reaction is exothermic and a high equilibrium conversion of TDA is expected due to its large reaction equilibrium constant. Secondly, under the suitable reaction conditions, 130 °C, 7 h, and molar ratio of TDA/zinc acetate/urea/sulfolane 1/0.05/3.5/10, TDA conversion is 54.3%, and TBU yield and selectivity are 39.8% and 73.3% respectively. Lastly, the synthesis of TBU is a 1st order reaction with respect to TDA and the reaction kinetics model is established. This work will provide useful information for commercializing the urea route to toluene-2,4-dicarbamate (TDC).展开更多
The crystal structure of [Ni(C5H2N2O4)(2, 2?bipy)(H2O)2]?H2O 1 has been determined by X-ray diffraction. Crystal data: triclinic system, space group P with a = 7.9424(3), b = 9.9417(3), c = 12.1867(3) ? a = 84.771(1),...The crystal structure of [Ni(C5H2N2O4)(2, 2?bipy)(H2O)2]?H2O 1 has been determined by X-ray diffraction. Crystal data: triclinic system, space group P with a = 7.9424(3), b = 9.9417(3), c = 12.1867(3) ? a = 84.771(1), b = 77.375(2), g = 68.993(2)? C15H18N4O8Ni, Mr = 440.7, V = 876.16(5) 3, Z = 2, Dc = 1.672 g/cm3, F(000) = 456, m(MoKa) = 1.162 mm-1, the final R = 0.0464 and wR = 0.1055 for 3026 observed reflections with I > 2s(I). In the title compound, the nickel ion is coordinated by a nitrogen atom and an oxygen atom from the orotate ligand, two nitrogen atoms from 2, 2?bipy and two oxygen atoms from the coordinated water molecules in a distorted octahedral geometry. The presence of intermolecular hydrogen bonding and p-p stacking interaction of aromatic rings from 2, 2?bipy results in a 3D structure.展开更多
As an oral chemotherapy prodrug,tegafur,can be converted to 5-fluorouracil,which is activated to kill tumor cells mainly by the inhibition of thymidylate synthase.In the present study,we synthesized 20 new tegafur der...As an oral chemotherapy prodrug,tegafur,can be converted to 5-fluorouracil,which is activated to kill tumor cells mainly by the inhibition of thymidylate synthase.In the present study,we synthesized 20 new tegafur derivatives containing amino acid ester groups by substitution,hydrolysis,and condensation.Their structures were confirmed by 1H NMR,13C NMR,and H RMS,and their inhibitory effects on tumor cell growth were studied.The results showed that some of the compounds had good anti-tumor activity.展开更多
基金Supported by the National Natural Science Foundation of China (20976035, 21076059) the Natural Science Foundation of Hebei Province (B2010000019)
文摘Toluene-2,4-bisurea (TBU) is an important intermediate for urea route to dimethyl toluene-2,4-dicarbamate and the study on TBU synthesis via the reaction of 2,4-toluene diamine (TDA) and urea is of great significance. Firstly, thermodynamic analysis shows that the reaction is exothermic and a high equilibrium conversion of TDA is expected due to its large reaction equilibrium constant. Secondly, under the suitable reaction conditions, 130 °C, 7 h, and molar ratio of TDA/zinc acetate/urea/sulfolane 1/0.05/3.5/10, TDA conversion is 54.3%, and TBU yield and selectivity are 39.8% and 73.3% respectively. Lastly, the synthesis of TBU is a 1st order reaction with respect to TDA and the reaction kinetics model is established. This work will provide useful information for commercializing the urea route to toluene-2,4-dicarbamate (TDC).
基金This project was supported by the Natural Science Foundation of China and Chinese Academy of Sciences
文摘The crystal structure of [Ni(C5H2N2O4)(2, 2?bipy)(H2O)2]?H2O 1 has been determined by X-ray diffraction. Crystal data: triclinic system, space group P with a = 7.9424(3), b = 9.9417(3), c = 12.1867(3) ? a = 84.771(1), b = 77.375(2), g = 68.993(2)? C15H18N4O8Ni, Mr = 440.7, V = 876.16(5) 3, Z = 2, Dc = 1.672 g/cm3, F(000) = 456, m(MoKa) = 1.162 mm-1, the final R = 0.0464 and wR = 0.1055 for 3026 observed reflections with I > 2s(I). In the title compound, the nickel ion is coordinated by a nitrogen atom and an oxygen atom from the orotate ligand, two nitrogen atoms from 2, 2?bipy and two oxygen atoms from the coordinated water molecules in a distorted octahedral geometry. The presence of intermolecular hydrogen bonding and p-p stacking interaction of aromatic rings from 2, 2?bipy results in a 3D structure.
基金Science and Technology Program of Shandong Academy of Medical Sciences(Grant No.2016-5)National Innovation and Entrepreneurship Training Program for College Students(Grant No.201810427013)。
文摘As an oral chemotherapy prodrug,tegafur,can be converted to 5-fluorouracil,which is activated to kill tumor cells mainly by the inhibition of thymidylate synthase.In the present study,we synthesized 20 new tegafur derivatives containing amino acid ester groups by substitution,hydrolysis,and condensation.Their structures were confirmed by 1H NMR,13C NMR,and H RMS,and their inhibitory effects on tumor cell growth were studied.The results showed that some of the compounds had good anti-tumor activity.