An efficient and environmental-friendly one-pot procedure has been developed for the synthesis of 1,3,4-oxadiazole-5- thioethers by the reaction of acylhydrazine with carbon disulfide and organic halides or α, β-uns...An efficient and environmental-friendly one-pot procedure has been developed for the synthesis of 1,3,4-oxadiazole-5- thioethers by the reaction of acylhydrazine with carbon disulfide and organic halides or α, β-unsaturated carbonyl compounds. The reactions were carried out in water in the presence of potassium phosphate within 2-4 h to afford the expected products in excellent yields.展开更多
The new copper(II) complex Cu(C13H9N3O2Br)2H2O (N-(2-hydroxy-5-bromo- benzoyl)-N-(picolinylidene)hydrazine is abbreviated as HL ) was obtained from the refluxing solution of Cu(CH3COO)2H2O and HL in the ethanol-N, N-d...The new copper(II) complex Cu(C13H9N3O2Br)2H2O (N-(2-hydroxy-5-bromo- benzoyl)-N-(picolinylidene)hydrazine is abbreviated as HL ) was obtained from the refluxing solution of Cu(CH3COO)2H2O and HL in the ethanol-N, N-dimethylformamide mix solvent. Crystal data: triclinic, space group P , a = 10.8620(3), b = 11.7453 (3), c = 12.4417(2) ? ?= 62.255(0), ?= 79.097(2), ?= 86.764(2)? V = 1378.52(6) ?, Z = 2, Mr = 719.835, Dc = 1.734 g/cm3, F(000) = 714, (MoK) = 3.739 mm-1, T = 293(2) K, final R = 0.0594 and wR = 0.1416 for 2943 observed reflections with I > 2.0(I). The structure of Cu(C13H9N3O2Br)2H2O has been determined by X-ray analysis and revealed that two L-1 ligands coordinate to the copper(Ⅱ) ion through two oxygen and two nitrogen atoms from the hydrazine groups and two pyridine nitrogen atoms to form an elongated and distorted square-bipyramidal environment for Cu(Ⅱ). The complex is also characterized by 1H NMR spectroscopies展开更多
Under microwave irradiation, with dimethypyridine-2,6-dicarboxylate and hydrazine hydrate as raw materials, 2,6-pyridine dicarboxylic hydrazine was produced. At the same time, the influence factors of production rate,...Under microwave irradiation, with dimethypyridine-2,6-dicarboxylate and hydrazine hydrate as raw materials, 2,6-pyridine dicarboxylic hydrazine was produced. At the same time, the influence factors of production rate, such as microwave radiation time, reaction power, the amount of dimethypyridine-2,6-dicarboxylate and hydrazine hydrate was further explored. Through the orthogonal experiments, better technology conditions were found which make the synthetic process turn from the new type of microwave technology.展开更多
The title compound N-[1-(4-chlorophenyl)-1,4-dihydro-4-oxe-6-methylpyridazine- 3-carbonyl]-N(-benzoylhydrazine was prepared by the reaction of 1-(4-chlorophenyl)-1,4- dihydro-4-oxe-6-methylpyridazine-3-carboxylic acid...The title compound N-[1-(4-chlorophenyl)-1,4-dihydro-4-oxe-6-methylpyridazine- 3-carbonyl]-N(-benzoylhydrazine was prepared by the reaction of 1-(4-chlorophenyl)-1,4- dihydro-4-oxe-6-methylpyridazine-3-carboxylic acid with chloroformate ethyl ester and benzoyl hydrazine in the presence of triethylamine. The crystal structure ([C19H15ClN4O3]2·C2H5OH, Mr =811.67) has been determined by X-ray crystal structural analysis. The crystal is monoclinic, space group P21/c, with unit cell parameters a=13.296(3), b=17.155(3), c=17.459(3)?,β=98.959(4), Z=4, V=3934(1) ?3, Dc=1.371g/cm3, F(000)=1688, μ(MoKα)=0.226 mm-1, R=0.0495, wR=0.1348 for 3345 observed reflections (I >2σ(I)). The hydrogen bonds N(3)－H…O(1) , N(7)－H…O(4), and N(8)－H…O(2) can be observed.展开更多
The C-terminal conjugate of ubiquitin with 7-amino-4-methylcoumarin （Ub-AMC） is an important probe for fluorescencebased analysis of deubiquitinating enzyme （DUB） activity. It is important to develop more efficien...The C-terminal conjugate of ubiquitin with 7-amino-4-methylcoumarin （Ub-AMC） is an important probe for fluorescencebased analysis of deubiquitinating enzyme （DUB） activity. It is important to develop more efficient methods for the preparation of Ub-AMC because the currently available technology is still expensive for scaled-up production. In the present work we report an efficient strategy for total chemical synthesis of Ub-AMC through ligation of peptide hydrazides. Three peptide segments are assembled via N-to-C sequential ligation and the resulting product is converted to Ub-AMC via TCEP-mediated desulfurization. The synthetic Ub-AMC is shown to have expected biological functions throug展开更多
基金Natural Science Foundation of China (Grant No.20672009)the Major State Basic Research Development Program(Grant No.2004CB719900).
文摘An efficient and environmental-friendly one-pot procedure has been developed for the synthesis of 1,3,4-oxadiazole-5- thioethers by the reaction of acylhydrazine with carbon disulfide and organic halides or α, β-unsaturated carbonyl compounds. The reactions were carried out in water in the presence of potassium phosphate within 2-4 h to afford the expected products in excellent yields.
基金Acknowledgments: The authors thank the Chinese Academy of Sciences the National Science Foundation of China (20073048)the NSF of Fujian for financial support
文摘The new copper(II) complex Cu(C13H9N3O2Br)2H2O (N-(2-hydroxy-5-bromo- benzoyl)-N-(picolinylidene)hydrazine is abbreviated as HL ) was obtained from the refluxing solution of Cu(CH3COO)2H2O and HL in the ethanol-N, N-dimethylformamide mix solvent. Crystal data: triclinic, space group P , a = 10.8620(3), b = 11.7453 (3), c = 12.4417(2) ? ?= 62.255(0), ?= 79.097(2), ?= 86.764(2)? V = 1378.52(6) ?, Z = 2, Mr = 719.835, Dc = 1.734 g/cm3, F(000) = 714, (MoK) = 3.739 mm-1, T = 293(2) K, final R = 0.0594 and wR = 0.1416 for 2943 observed reflections with I > 2.0(I). The structure of Cu(C13H9N3O2Br)2H2O has been determined by X-ray analysis and revealed that two L-1 ligands coordinate to the copper(Ⅱ) ion through two oxygen and two nitrogen atoms from the hydrazine groups and two pyridine nitrogen atoms to form an elongated and distorted square-bipyramidal environment for Cu(Ⅱ). The complex is also characterized by 1H NMR spectroscopies
文摘Under microwave irradiation, with dimethypyridine-2,6-dicarboxylate and hydrazine hydrate as raw materials, 2,6-pyridine dicarboxylic hydrazine was produced. At the same time, the influence factors of production rate, such as microwave radiation time, reaction power, the amount of dimethypyridine-2,6-dicarboxylate and hydrazine hydrate was further explored. Through the orthogonal experiments, better technology conditions were found which make the synthetic process turn from the new type of microwave technology.
基金the National Nature Science Foundation (29832050).
文摘The title compound N-[1-(4-chlorophenyl)-1,4-dihydro-4-oxe-6-methylpyridazine- 3-carbonyl]-N(-benzoylhydrazine was prepared by the reaction of 1-(4-chlorophenyl)-1,4- dihydro-4-oxe-6-methylpyridazine-3-carboxylic acid with chloroformate ethyl ester and benzoyl hydrazine in the presence of triethylamine. The crystal structure ([C19H15ClN4O3]2·C2H5OH, Mr =811.67) has been determined by X-ray crystal structural analysis. The crystal is monoclinic, space group P21/c, with unit cell parameters a=13.296(3), b=17.155(3), c=17.459(3)?,β=98.959(4), Z=4, V=3934(1) ?3, Dc=1.371g/cm3, F(000)=1688, μ(MoKα)=0.226 mm-1, R=0.0495, wR=0.1348 for 3345 observed reflections (I >2σ(I)). The hydrogen bonds N(3)－H…O(1) , N(7)－H…O(4), and N(8)－H…O(2) can be observed.
基金National Basic Research Program of China (973 program, 2013CB932800)the National Natural Science Foundation of China (NSFC, 31100524 to M.Z., 31170817 for C.T., and 20972148 to L.L.)
文摘The C-terminal conjugate of ubiquitin with 7-amino-4-methylcoumarin （Ub-AMC） is an important probe for fluorescencebased analysis of deubiquitinating enzyme （DUB） activity. It is important to develop more efficient methods for the preparation of Ub-AMC because the currently available technology is still expensive for scaled-up production. In the present work we report an efficient strategy for total chemical synthesis of Ub-AMC through ligation of peptide hydrazides. Three peptide segments are assembled via N-to-C sequential ligation and the resulting product is converted to Ub-AMC via TCEP-mediated desulfurization. The synthetic Ub-AMC is shown to have expected biological functions throug
