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噻唑环及其衍生物广泛存在于具有生物活性的分子中[1]可用于抗生素和消炎药的制备[2]。本文合成的几种噻唑基衍生物—类以HIV蛋白酶为靶点的新型抗艾滋病药物利托那韦的重要中间体[3-5],对其合成工艺的研究具有较实际的意义。噻唑环衍生物可通过α-卤代羰基化合物与硫代酰胺缩合而成[6],α-巯基酮与腈缩合反应得到,也可采用醛与半胱氨酸缩合,再与二氧化锰作用得噻唑类化合物[7]。本文采用α-氯代羰基类化合物与硫代酰胺缩合而得三种噻唑类化合物,产率较为理想。1合成路线设计合成路线设计可表示如下图1图1目标化合物的合成路线F ig.1 The … 相似文献
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在不加任何催化剂条件下, 2-(12-苯并吖啶酮)-乙酸(BAAA)与N,N′-羰基双咪唑(CDI)缩合生成新型荧光探针5-羰基咪唑苯并吖啶酮(IEBA). IEBA在DMF溶剂中与胺类化合物形成的酰胺类衍生物不仅可发出强烈的荧光, 还具有较高的质谱离子化能力. 该衍生物在乙腈和甲醇-水溶液中的百分离子化δ值分别在0~57.32% 和0~62.14%范围内. 最大激发和发射波长λex/λem=272 nm/505 nm. 12种胺类衍生物的荧光检出限范围为0.15~0.50 ng/mL, 在线APCI-MS检出限范围为1.43~8.51 ng/mL. 相似文献
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使用密度泛函理论(DFT)B3LYP/6-31G(d)方法优化得到了3(5)-(9-蒽基)吡唑及其衍生物的基态(S0)分子结构, 使用单激发组态相互作用(CIS)/6-31G(d)方法优化得到这些分子的第一单重激发态(S1)的几何结构, 并使用含时密度泛函理论(TD-DFT)B3LYP/6-311++G(d,p)方法计算了它们的吸收和发射光谱. 计算结果表明, 与3(5)-(9-蒽基)吡唑相比, 无论取代基是吸电子基团还是供电子基团, 衍生物的吸收和发射峰均发生红移, 并且当取代基―R=―BH2, ―CCl3, ―CHO, ―NH2时衍生物有较长的吸收波长和发射波长. 相似文献
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由马来酐、邻苯二甲酸酐合成(硫)脲衍生物 总被引:1,自引:0,他引:1
马来酐和邻苯二甲酸酐的含氮衍生物具有很强的生理活性,它们作为驱鼠剂,除草剂,植物生长调节剂已有报导。我们以马来酐和邻苯二甲酸酐为原料合成了16种(硫)脲衍生物并测定了它们的结构,这些化合物均未见文献报导。其合成路线如下: 相似文献
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将邻羟苯基引入1,2,3-三唑结构中, 设计合成了10个1-(4-取代苯基)-4-苯基-5-取代-1,2,3-三唑类衍生物. 首先, 以对位取代的芳胺为原料, 经重氮化、叠氮化、闭环和缩合反应制得1-(4-取代苯基)-4-苯基-5-水杨醛亚胺-1,2,3-三唑类衍生物(3a~3e), 再用硼氢化钠还原制得1-(4-取代苯基)-4-苯基-5-(2-羟基苄基)氨基-1,2,3-三唑类衍生物(4a~4e). 目标化合物的结构经核磁、IR及元素分析确认. 抑菌活性测试表明, 当质量浓度为0.1 mg/L时, 除化合物3e和4e外, 所有化合物对白色念球菌的抑菌率均达95%以上, 对大肠杆菌的抑菌率达85%以上, 具有强抑菌活性, 表明该类化合物在抗菌药物开发方面有重要应用价值. 相似文献
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The synthesis of novel 5-(phenylamino)-, 5-(benzylamino)-, and 5-(phenethylamino) derivatives of 1-benzyluracil-containing
different substituents in the aromatic nucleus has been carried out. Using the Hilbert-Johnson reaction it was found that
N(1)-monosubstitution can be achieved via alkylation of trimethylsilyl derivatives of 5-(arylamino)uracils using benzyl bromide.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 887–892, June, 2005. 相似文献
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5-(Bromomethylene)hydantoins, prepared from bromopyruvic acid and ureas in the presence of BF3, react with various nitrogen, phosphorus, sulfur, and carbon nucleophiles by addition-elimination to give the corresponding 5-(substituted-methylene)hydantoins. The 5-(bromomethylene)hydantoins also undergo acid-catalyzed reactions with nucleophiles by addition-displacement and addition-elimination processes. 相似文献
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利用超声波分解Fe(CO)5,分解产物通过非均相沉淀获得Nd2Fe14B/Fe双相复合磁粉,采用放电等离子烧结技术(Spark Plasma Sintering,SPS)制备出致密的Nd2Fe14B/α-Fe双相复合磁体.研究发现,伴随着软磁相Fe名义含量的增加,硬磁相Nd2Fe14B颗粒表面包覆的纳米Fe颗粒明显增加,包覆更加均匀,双相复合磁体的最大磁能积(BH)m和剩磁Br逐渐增大,在Fe名义含量为15%时获得最佳磁性能:(BH)m=128.2 kJ·m-3(16.1 MGOe),Br=0.92 Hcj=607.35 kA·-1.当Fe名义含量超过15%时,纳米Fe在Nd2Fe14B颗粒表面团聚现象加剧,致使磁能积和剩磁下降. 相似文献
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选取模型化合物,用AMl MO方法从理论上研究了手性的5-(L-盖氧基)-2(5—H)-呋喃酮与偶极硝酮体系环加成反应的机理。优化了反应过程各驻点的几何构型,计算了反应的活化焓、活化熵和反应速率常数,结果表明,该反应为同面的协同过程,非对映专一性产物的形成估计是由于盖氧基及硝酮分子上苯取代基的空间效应所致。 相似文献
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5—(5—氯—2—吡啶偶氮)—2,4—二氨基甲苯吸光光度法测定微量镍研究 总被引:2,自引:0,他引:2
在SDS存在下 ,于 pH 5 .5~ 6.5水溶液中 ,5 (5 氯 2 吡啶偶氮 ) 2 ,4 二氨基甲苯 (5 Cl PADAT)与镍 (Ⅱ )形成稳定的紫红色配合物 ,其最大吸收波长位于 5 4 5nm处 ,表观摩尔吸光系数为 1.0 2× 10 5L·mol- 1·cm- 1,配合物中镍与试剂的组成比为 1∶2 ,镍浓度在 0~ 4 μg/ 10ml范围内服从比耳定律。在硫脲、氟化铵和焦磷酸钠存在下 ,方法具有良好的选择性 ,用于镁合金、矿样和钢样中微量镍的测定 ,结果满意 相似文献
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《Analytical letters》2012,45(1-2):99-112
Abstract A spectrophotometric study of the Pd(II) complex of a reagent 2-(5-Bromo-2-Pyridylazo)-5-(diethylamino)-Phenol (5-Br-PADAP) is presented. A violet complex is formed at pH 3.53, and shows maximal absorbance at 585 nm with molar absorptivity of 3.86 × 104 1. mol?1 cm?1. Beer's law is obeyed up to 50 μ of Pd(II). The method offers the advantages of simplicity, high precision, requires no extraction and is very selective, where 5.0 mg Pt(VI) and 0.3 mg Au(III) ions do not interfere. 相似文献
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S. Gargadennec B. Legouin J.-L. Burgot 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1721-1726
The preparation of new 5-formyl-, 5-acetyl- and 5-propionyl-1,2-dithiole-3-ones by oxidation of the corresponding 1,2-dithiole-3-thiones with mercuric acetate is described. 相似文献
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5-Hydroxymethyl-2-furfurylamine (5-HMFA) as an important 5-HMF derivative has been widely utilized in the manufacture of diuretics, antihypertensive drugs, preservatives and curing agents. In this work, an efficient chemoenzymatic route was constructed for producing 5-(hydroxymethyl)furfurylamine (5-HMFA) from biobased D-fructose in deep eutectic solvent Betaine:Glycerol–water. The introduction of Betaine:Glycerol could greatly promote the dehydration of D-fructose to 5-HMF and inhibit the secondary decomposition reactions of 5-HMF, compared with a single aqueous phase. D-Fructose (200 mM) could be catalyzed to 5-HMF (183.4 mM) at 91.7% yield by SG(SiO2) (3 wt%) after 90 min in Betaine:Glycerol (20 wt%), and at 150 °C. E. coli AT exhibited excellent bio-transamination activity to aminate 5-HMF into 5-HMFA at 35 °C and pH 7.5. After 24 h, D-fructose-derived 5-HMF (165.4 mM) was converted to 5-HMFA (155.7 mM) in 94.1% yield with D-Ala (D-Ala-to-5-HMF molar ratio 15:1) in Betaine:Glycerol (20 wt%) without removal of SG(SiO2), achieving a productivity of 0.61 g 5-HMFA/(g substrate D-fructose). Chemoenzymatic valorization of D-fructose with SG(SiO2) and E. coli AT was established for sustainable production of 5-HMFA, which has potential application. 相似文献
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In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, 5-(l-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of new enantiomerically pure compounds, 5–(l-menthyloxy)-4-substituted-3-chloro-2(5H)-furanones, were obtained in good yields with d. e. ? 98% under mild conditions. 相似文献
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3-Chloro-2-polyfluoroalkyl- and 3-chloro-6-nitro-2-polyfluoroalkylchromones were synthesized. These compounds react with N2H4·2HCl on boiling in ethanol to form 4-chloro-3(5)-(2-hydroxyaryl)-5(3)-polyfluoroalkylpyrazoles. 相似文献