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51.
Data on drugs of the tetrazole series published over the last decade are reviewed. The use of tetrazoles as isosteric substituents
of various functional groups is examined.
Dedicated to outstanding scientist Prof. E. Lukevics on his 70th birthday.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 3–13, January, 2007. 相似文献
52.
本文综述了前列环素及其类似物的合成。类似物包括有7-羰基—、10,10-二氟—、5-氯—,4-羰基—、6,9-硫—、6,9-氮—,6 a-碳—前列环素以及苯前列环素等。前列环素及其类似物是一类具有抑制血小板聚集的生物活性化合物。 相似文献
53.
54.
2-Amino-and 2-hydrazino-5-(3 or 4-pyridyl)-1, 3, 4-oxadiazoles [IIi-k] have been prepared by racting 2-chloro derivatives with the corresponding amines or hydrazines, the 2-hydrazino (IIi-k) compounds that obtained were heated with carbon disulphide and alcoholic potassium hydroxide where 5-(3 or 4-pyridyl)-1,3,4-oxadiazolo (2,3-C)-1,2,4-triazole 5-thione (IIIa-c) were obtained, the given structures were biologically screened. 相似文献
55.
Mu-Shih Lin Kuen-Tay Jeng 《Journal of polymer science. Part A, Polymer chemistry》1992,30(9):1941-1951
Poly(ethylene glycol) diacrylate was synthesized from poly(ethylene glycol) of molecular weight 600 with acryloyl chloride in a molar ratio of 1:2. Poly(ethylene glycol) diacrylate (PEGDA) was then blended with diglycidyl ether of bisphenol A (DGEBA) in various ratios, followed by curing with 2,2′-azobisisobutyronitrile (AIBN) and isophronediamine (IPDA) simultaneously. Viscosity changes before and during IPN formation were examined with a Brookfield viscometer. Formation of H-bonding and functional group changes were investigated with FTIR. Exothermic curing thermograms were recorded with dynamic DSC. Optically clear IPNs thus obtained were characterized with rheometric dynamic spectroscopy (RDS) and scanning electron microscopy (SEM) to check possible compatibility of the two networks. Experimental results revealed that during IPN formation hydrogen bonds between PEGDA and DGEBA and interlock of networks had profound effect on viscosity change and pot-life. Complete compatibility of the IPNs was found as DGEBA content was higher than 50% by weight. The compatibility between PEGDA and DGEBA networks was evidenced from inner shift of a single damping peak in RDS. In the meantime, SEM micrographs confirmed the coincidence with the result of RDS © 1992 John Wiley &Sons, Inc. 相似文献
56.
57.
J. Tolchard 《Journal of solid state chemistry》2007,180(10):2808-2815
The chemical and physical compatibility of SrCeO3 is investigated with respect to LaMO3 (M=Mn, Fe, Co) and La2−xSrxNiO4 (x=0, 0.8), via the reaction of fine-grained powder compacts and solid-state diffusion couples. Compositions were chosen so as to give predictive insight into possible candidate materials for all-oxide electrochemical devices. Results show the primary reaction in these systems to be the dissolution of SrO from SrCeO3 into the LaMO3/La2−xSrxNiO4, and corresponding formation of La-doped CeO2. Reaction kinetics are observed to be relatively fast, with element profiles suggesting the diffusion of Sr2+ in ceria to be surprisingly rapid. It is demonstrated that perovskite starting materials represent poor candidates for use with SrCeO3, reacting completely to form Ruddlesden-Popper/K2NiF4 type oxides. Reaction with La2NiO4 is less pronounced, and formation of secondary phases suppressed for the composition La1.2Sr0.8NiO4. It is thus concluded that Ruddlesden-Popper type oxides represent good candidate materials for use with a SrCeO3-based electrolytes when doped with appropriate levels of Sr. 相似文献
58.
肝素化壳聚糖季铵盐/壳聚糖复合膜抗凝血性能的研究 总被引:13,自引:1,他引:13
以壳聚糖季铵盐,壳聚糖为基本原材料,选用戊二醛为交剂剂及固定剂,制备一种物理机械性能较优的抗凝血材料。探讨了戊二醛及肝素钠两者用量对肝素化程度及血液生的影响。 相似文献
59.
InteractionbetweenMetalinMetalloEnzymeandSmallBiologicalMolecules¥HuJie-Han;ShuZan-Yong;TaoLi-Mei;ChengGuo-Bao(DalianInstitut... 相似文献
60.
以芳香基三唑类杀菌剂三唑酮为先导物设计并合成了5个含N,N-二烷基二硫代氨基甲酸酯的芳香三唑类化合物, 通过元素分析、红外光谱、核磁共振氢谱和质谱对其结构进行了表征. 用X射线单晶衍射测定了[α-(4-甲氧基苯甲酰基)-2-(1,2,4-三唑-1-基)]乙基-N,N-二甲基二硫代氨基甲酸酯的晶体结构, 晶体属于三斜晶系, 空间群, 晶胞参数为: a=0.73482(15) nm, b=1.1051(2) nm, c=1.1209(2) nm, α=90.32(3)°, β=101.97(3)°, γ=105.13(3)°, V=0.8578(3) nm3,
Z=2, Dc=1.357 g/cm3, F(000)=368, µ=0.324 mm-1. 生物测试结果显示这5种有机化合物都具有杀菌性和植物生长调节活性 相似文献