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951.
设计合成了具有降血糖活性的3-甲基-1-苯基-4-[4-[[5-甲基-2-(4-取代芳基)-噁唑-4-基]甲氧基]-芳亚甲(苄)基]}-2-吡唑啉-5-酮类化合物.用丁二酮单肟和(取代的)苯甲醛环合、氯化得到氯甲基噁唑衍生物,与对羟基苯甲醛或香兰醛缩合,再与3-甲基-1-苯基-2-吡唑啉-5-酮进行Knoevenagel反应及催化氢化得到目标化合物(Ⅰ和Ⅱ),共合成了16个未见文献报道的新化合物,并利用元素分析、IR、MS和1HNMR确证了化合物的结构.初步药理试验结果表明,所合成的化合物有抑制血糖升高的倾向以及能明显加强和延长外源性胰岛素的降血糖作用,其中化合物Ⅰb,Ⅰd和Ⅰf尤为突出,说明这类化合物可能有增强胰岛素敏感性的作用. 相似文献
952.
LIU Xing-Quan WU Yu-Tang JIA Zhao-XiaChengdu Institute uf Organic ChemistryAcademia SinicaChengdu Sichuan To whom correspondence should be addressed. 《天然气化学杂志》1995,(1)
1 , 5-diazabicyclo['1, 3, 0]non-5-ene(DBN) has been synthesized in our laboratory, and its catalytic activity and selectivity for methanol carbonylation to methyl formate (MF) have been studied. The experimental results have demonstrated that the synthetic processes of DBN used for the present work are reasonable and feasible. The total yield of three steps of DBN synthsis is approximate to 80%. The activity evaluation has shown that DBN can effectively catalyze the carbonylation reaction of methanol in the presence of propylene oxide (PO) promoter. PO-promoted DBN is a novel catalytic system superior to sodium methoxide. 相似文献
953.
Synthesis and Crystal Structure of Ag2(admtrz)2(CF3CO2)2(admtrz=4—amino—3,5—dimethyl—1,2,4—triazole)
1 INTRODUCTION Transition metal complexes bridged by 1, 2, 4-triazole group can produce interesting structures and specific properties[1]. Many attempts have been made to synthesize a variety of complexes with paramagnetic centers by using such ligands, and their structures and magnetic properties have been characterized[2]. However, the polynuclear Ag(I) complexes bridged by 1, 2, 4-triazole have been poorly studied[3]. Recently, we have prepared a series of silver(I) triazole complex… 相似文献
954.
955.
The title compound C20H30N4O6, Mr = 422.48)was synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in the triclinic system, space group P ī with cell parameters: a = 8.330(2), b = 8.468(2), c = 16.017(3) A, α = 97.30(3), β = 92.33(3), γ = 103.94(3)o, V = 1084.7(4) A3, Dc = 1.294 g/cm3, Z = 2, F(000) = 452 and μ = 0.096 mm-1. The structure was refined to R = 0.0483 for 3732 observed reflections with I>2(I) and wR = 0.1335 for 4828 unique reflections. The hydantoin rings are planar and the two ring planes of one molecule are paralleled to each other. 相似文献
956.
1 INTRODUCTION Organic-inorganic hybrid materials and polyoxo-metalates have received much attention because of their intriguing structural diversity and potential applications in molecular adsorption, ion exchange, heterogeneous catalysis and nanotech nology as well as in electrical, magnetic and photochemical areas[1, 2]. One of the important ad- vances in the design of new organic-inorganic hybrid materials is utilizing poly- oxometalates’ coordination ability to produce poly- oxoanio… 相似文献
957.
非晶态NiP(B)/Al2O3催化一氧化碳,水和氧气合成过氧化氢 总被引:1,自引:0,他引:1
Hydrogenperoxideisagreenoxidantwithgreatpotentialformuchapplication .Thepresentproduc tionofhydrogen peroxiderequiressevereconditionsand generates pollutants .AlternativesynthesesarerequiredandthesynthesisofH2 O2 fromCO ,H2 OandO2 isverypromising .AsshowninEq(1) ,thesynthesisisthermodynamicallyfavored :CO +H2 O +O2 H2 O2 +CO2 (1)ΔG02 98=- 134kJ/mol ThereactionwasfirstreportedbyZudinetal[1]whousedpalladiumtriphenylphosphaneasacatalyst.Bianchietal[2 ] usedabiphasesystemforthesynthe … 相似文献
958.
邻二甲苯…Ar, N2, NH3(ND3)范德华复合物的共振双光子电离光谱 总被引:2,自引:0,他引:2
在超声分子束中,使用双光子共振电离光谱技术和飞行时间质谱技术研究了复合物邻二甲苯…Ar.N2,NH3(ND3).通过理论计算及同位素光谱效应.合理地归属了这些复合物的光谱.并由此获得这些复合物分子问各种模式的振动频率. 相似文献
959.
Four chiral polymers P-1, P-2, P-3 and P-4 were synthesized by the polymerization of (S)-2,2'-dioctoxy-1,1'- binaphthyl-6,6'-boronic acid (S-M-3) with (S)-6,6'-dibromo-1,1'-binaphthol (S-M-1), (R)-6,6'-dibromo-1,1'- binaphthol (R-M-1), (S)-3,3'-diiodo-1,1'-binaphthol (S-M-2) and (R)-3,3'-diiodo-1,1'-binaphthol (R-M-2) under Pd-catalyzed Suzuki reaction, respectively. All four polymers can show good solubility in some common solvents due to the nonplanarity of the polymers in the main chain backbone and flexible alkyl groups in the side chain. The analysis results indicate that specific rotation and circular dichroism (CD) spectral signals of the alternative S-S chiral polymers P-1 and P-3 are larger than those of S-R chiral polymers P-2 and P-4, but their UV-Vis and fluorescence spectra are almost similar. The results of asymmetric enantioselectivity of four polymers for diethylzinc addition to benzaldehyde indicate that catalytically active center is (R) or (S)-1, 1'-binaphthol moieties. 相似文献
960.
聚(丁二酸丁二酯-co-丁二酸丙二酯)的等温结晶行为研究 总被引:1,自引:0,他引:1
以1,4-丁二酸、1,4-丁二醇和1,3-丙二醇为原料通过直接熔融缩聚法合成了聚丁二酸丁二酯(PBS),聚丁二酸丙二酯(PPS)和聚(丁二酸丁二酯-co-丁二酸丙二酯)(PBSPS)等脂肪族聚酯.利用1H-NMR,WAXD,DSC和POM等研究了聚酯的结晶结构和结晶动力学过程等结晶行为.PBSPS的结晶晶型与PBS一致,说明只有丁二酸丁二酯(BS)单元结晶而丁二酸丙二酯(PS)单元处于无定形区.聚酯等温结晶后,在升温熔融过程中出现了多重熔融峰.分析表明多重熔融峰主要来自于聚酯升温过程中的熔融-重结晶行为.利用Avrami方程分析了聚酯的等温结晶动力学,Avrami指数n为2.2~2.8,说明聚酯等温结晶时主要以异相成核的三维生长方式进行;随着PS单元的增多,聚酯的表观结晶活化能升高,也就是说BS单元的结晶变得困难.POM观察到聚酯等温结晶时都出现了环带球晶现象,球晶形态会随着结晶温度和化学结构差异而改变. 相似文献