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新的核苷衍生物N2,N3-亚乙烯基腺嘌呤核苷的合成 总被引:4,自引:0,他引:4
描述了一条有效的合成新的荧光核苷衍生物N2,N3-亚乙烯基腺苷的合成路线.实验中首先通过6步制备了N2,N3-亚乙烯基鸟苷,然后经过氯化,再氨化得到标题化合物.标题化合物和新的中间化合物的结构分别通过1H NMR, MS和HRMS进行了确证,标题化合物的荧光性质初步得到证实. 相似文献
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Bao-qing Shentu Ji-peng Li Zhi-xue Weng 《高分子科学》2006,(4):345-351
The effect of N,N,N',N'-tetraalkyl terephthalamide (TATA) on the non-isothermal crystallization and melting characteristics ofpolypropylene (PP) was studied. The addition of TATA can lead to the formation ofβ-crystal PP. With the increase in TATA concentration the degree of crystallinity for β-crystal PP increased significantly, and that for a-crystal PP decreased, which indicated that TATA effectively induced the formation of β-crystal PP. WAXD also revealed the existence of β-crystal PP after the introduction of TATA into PP. PP containing TATA crystallized at a temperature range of 5-10℃ higher than that of pure PP, and the half-crystallization time (t1/2) and Avrami exponent (n) of PP at the same cooling rate were decreased by the addition of TATA, indicating that TATA influenced the crystallization rate and crystallization growth mode of PP. The rate constant of crystallization of PP containing TATA (Zc) was larger than that of pure PP, which further indicated that the crystallization of PP was accelerated by the addition of TATA. 相似文献
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Structural Investigations on the Oxidenitrides SrTaO2N, CaTaO2N and LaTaON2 by Neutron and X‐ray Powder Diffraction The crystal structures of the perovskite related oxidenitrides SrTaO2N, LaTaON2 and CaTaO2N have been determined with special regard to the structures of the respective anionic partial structure. The structure refinements were performed by individual Rietveld analyses of both X‐ray and neutron powder diffractograms and in addition by joint refinements in order to confirm the results. Both refinement methods yield consistent structure solutions. At least the first two compounds have fully ordered anionic sublattices. The crystal structure of SrTaO2N has been solved in the space group I4/mcm (a = 5.7049(3) Å, c = 8.0499(5) Å, Rp = 0.0706, Rwp = 0.0904, reflections: 70 (neutrons)/36 (X‐ray), R(F2)(n) = 0.147, R(F2)(X) = 0.0952), with an ordered anionic partial structure. LaTaON2 crystallizes monoclinic (C2/m, a = 8.0922(3) Å, b = 8.0603(2) Å, c = 5.7118(2) Å, β = 134.815(1)°, Rp = 0.0592, Rwp = 0.0766, reflections: 235(n)/113(X), R(F2)(n) = 0.0944, R(F2)(X) = 0.165) and also shows a totally ordered distribution of the anions. In the case of CaTaO2N (Pnma, a = 5.6239(3) Å, b = 7.8954(4) Å, c = 5.5473(3) Å, Rp = 0.0503, Rwp = 0.0656, reflections 206(n)/110(X), R(F2)(n) = 0.0985, R(F2)(X) = 0.0405) slightly unbalanced displacement parameters (neutron data, ordered O/N distribution model) hint at a partial exchange of oxygen and nitrogen. 相似文献
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The preparation of benzoyl-protectcd N,N′-ethylenebis(2-mercaptopropanamide) (H4emp) and its ligand-exchange reaction with ReO2(en)2Cl are described. Three diastereomers, [syn-ReO(meso-emp)]; [anti-ReO(meso-emp)]-, and a pair of cnantiomers, [ReO(rac-emp)]-, were formed due to syn and anti orientation of the two methyl groups of the ligand relative to the ReO core. The diastereomers were separated by reverse phase C18 semipreparative HPLC and isolated as salts of [Ph4As][ReO-(emp)]. The structures of [Ph4 As][ReO(meso-emp)] were determined by single-crystal X-ray analyses. [Ph4As][syn-ReO(mesocmp)]H2O crystallizes in triclinic space group Pl with a = 10.326(3) Å, b = 13.672(4) A, c = 14.023(5) Å, α = 61.20(2)°, β =74.74(3)°, γ= 75.68(2)° V = 1656.6(8) Å3, Z = 2, Dc = 1.676 gmL?1, F(000) = 824 and R = 0.0329 for 5877 unique reflections. For (he complex [Ph4As][anti-ReO(meso-emp)], the crystal data are: monoclinic, space group P21/n, a = 9.128(2) Å, b = 24.284(7) Å, c = 14.112(4) Å, β = 93.41(2)° V = 3122.5(15) À3, Z = 4, Dc = 1.740 gmL?1, F(000) = 1608 and R = 0.0361 for 5487 unique reflections. In both structures the rhenium atom is penta-coordinated and in an approximately square pyramidal environment. 相似文献
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Qichen Huang Zheming Wang Qianli Chu Shizheng Zhu 《Journal of inclusion phenomena and macrocyclic chemistry》2006,54(3-4):177-180
X-ray analysis has revealed that N,N,N′,N′-tetramethyl-ethylenediamine 1 form donor–acceptor complex 3 with 1-bromo-2-iodo-tetrafluoroethane 2, in which the N X (X = Br, I) distances are longer than the average covalent bond length between X and N, but are also definitively shorter than the sum of the corresponding van der Waals radii of X and N, thus that indicating weak interactions between the nitrogen and bromine or iodine atoms. In our experimental section, a valuable method for recrystallization and collect X-ray data from crystals that easily exhibit decay and can be cracked is reported. 相似文献
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偶氮化合物可用作非线性光学材料、激光盘信息存贮材料和现代科技中的油溶性染料[1].传统偶氮化合物的制备有重氮盐偶合和取代肼氧化等许多方法[2~4],其偶氮基两端一般联有烃基或芳环,而联有羰基的偶氮类化合物用通常方法难以制备.本文首次用N-溴代丁二酰亚... 相似文献
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Emily C. Monkcom Daniël de Bruin Annemiek J. de Vries Dr. Martin Lutz Dr. Shengfa Ye Prof. Dr. Robertus J. M. Klein Gebbink 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(16):5191-5204
We present the synthesis and coordination chemistry of a bulky, tripodal N,N,O ligand, ImPh2NNO t Bu ( L ), designed to model the 2-His-1-carboxylate facial triad (2H1C) by means of two imidazole groups and an anionic 2,4-di-tert-butyl-subtituted phenolate. Reacting K-L with MCl2 (M = Fe, Zn) affords the isostructural, tetrahedral non-heme complexes [Fe(L)(Cl)] ( 1 ) and [Zn(L)(Cl)] ( 2 ) in high yield. The tridentate N,N,O ligand coordination observed in their X-ray crystal structures remains intact and well-defined in MeCN and CH2Cl2 solution. Reacting 2 with NaSPh affords a tetrahedral zinc thiolate complex, [Zn(L)(SPh)] ( 4 ), that is relevant to isopenicillin N synthase (IPNS) biomimicry. Cyclic voltammetry studies demonstrate the ligand's redox non-innocence, where phenolate oxidation is the first electrochemical response observed in K-L , 2 and 4 . However, the first electrochemical oxidation in 1 is iron-centred, the assignment of which is supported by DFT calculations. Overall, ImPh2NNO t Bu provides access to well-defined mononuclear, monoligated, N,N,O-bound metal complexes, enabling more accurate structural modelling of the 2H1C to be achieved. 相似文献
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研究新型萃取剂从硝酸盐介质中萃取分离稀土元素对于后处理工艺具有重要意义。本文报道以甲苯为稀释剂,N,N,N′,N′-四丁基丙二酰胺(TBMA)从硝酸盐介质中萃取铈(Ⅲ)、镝(Ⅲ)、铒(Ⅲ)、镨(Ⅲ)、钐(Ⅲ)、铽(Ⅲ)、铥(Ⅲ)、镱(Ⅲ)的机理。考察了硝酸浓度、TBMA浓度、盐析剂浓度以及温度对上述三价镧系离子分配比的影响。得出萃合物的组成主要是三配体配合物M(NO3)3·3TBMA;计算出萃取反应的条件平衡常数、萃取平衡常数。温度效应研究表明萃取反应主要是焓驱动的。对萃取分离系数以及TBMA萃取三价镧系离子的规律进行了初步研究。 相似文献
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1 INTRODUCTION Schiff’s bases are well known ligands representedby many bi-, tri-, tetra-, and hexa-dentate example-es[1], but heptadentate ligands are relatively rare[2, . 3]We have reported a copper complex of tetradentateSchiff’s bases[4]… 相似文献
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Screening of N,N‐bidentate and N,N,N‐tridentate pyridine‐based ligands in the catalytic allylic oxidation of cyclic olefins 下载免费PDF全文
A variety of chiral N,N‐bidentate and N,N,N‐tridentate ligands based on the pyridine framework, namely C2‐symmetric dipyridylmethane and terpyridine, N‐(p‐toluensulfinyl)iminopyridines and two kinds of iminopyridines, has been assessed in the asymmetric copper(I)‐catalysed allylic oxidation of cyclic olefins. Catalytic activity and enantioselectivity were found to be highly dependent upon the framework of the ligands, which afforded cycloalkenyl benzoates in low to moderate yields and enantioselectivities. The best yields (up to 70%) and enantioselectivities (up to 53% enantiomeric excess) were obtained with an iminopyridine based on camphane and quinoline skeletons. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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N,N,N′,N′-tetra(2-nitrilethyl) ethane-1,2-diamine and N-(2-nitrilethyl)benzylamine hydrobromide were prepared by the addition reaction of acrylonitrile with corresponding amines, and the two structures were determined by X-ray single crystal diffraction. The two compounds crystallize in monoclinic system, and almost no classical hydrogen bond exists in the two crystal structures. 相似文献
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Arpan Mukherjee Tuhin Subhra Koley Ayan Chakraborty Dr. Kallol Purkait Dr. Arindam Mukherjee 《化学:亚洲杂志》2021,16(22):3729-3742
Half-sandwich RuII complexes, [(YZ)RuII(η6-arene)(X)]+, (YZ=chelating bidentate ligand, X=halide), with N,N and N,O coordination ( 1 – 9 ) show significant antiproliferative activity against the metastatic triple-negative breast carcinoma (MDA-MB-231). 3-aminobenzoic acid or its methyl ester is used in all the ligands while varying the aldehyde for N,N and N,O coordination. In the N,N coordinated complex the coordinated halide(X) is varied for enhancing stability in solution (X=Cl, I). Rapid aquation and halide exchange of the pyridine analogues, 2 and 3 , in solution are a major bane towards their antiproliferative activity. Presence of free −COOH group ( 1 and 4) make complexes hydrophilic and reduces toxicity. The imidazolyl 3-aminobenzoate based N,N coordinated 5 and 6 display better solution stability and efficient antiproliferative activity (IC50 ca. 2.3–2.5 μM) compared to the pyridine based 2 and 3 (IC50>100 μM) or the N,O coordinated complexes ( 7 – 9 ) (IC50 ca. 7–10 μM). The iodido coordinated, 6 , is resistant towards aquation and halide exchange. The N,O coordinated 7 – 9 underwent instantaneous aquation at pH 7.4 generating monoaquated complexes stable for at least 6 h. Complexes 5 and 6 , bind to 9-ethylguanine (9-EtG) showing propensity to interact with DNA bases. The complexes may kill via apoptosis as displayed from the study of 8 . The change in coordination mode and the aldehyde affected the solution stability, antiproliferative activity and mechanistic pathways. The N,N coordinated ( 5 and 6 ) exhibit arrest in the G2/M phase while the N,O coordinated 8 showed arrest in the G0/G1 phase. 相似文献
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合成了N,N′ 二 (2 吡啶基)四羧酸二酰亚胺,并纯化、调晶.对产物进行了元素分析和IR光谱研究(环状二酰亚胺的CO以双峰1708.8cm-1、1664 5cm-1).α晶型产物溶液的紫外可见光谱(最大吸收波长为526.00nm)和荧光光谱(最大发射波长为538.0nm)存在很好的镜像对称关系.薄膜紫外可见光谱图在450—570nm范围内,α晶型比β晶型有较强的吸收峰.X粉末衍射也反映出α晶型在2θ为25.5°、26.3°上的衍射峰强度分别为1954、2603.α、β晶型分别作为电荷产生材料制得的功能分离型有机光导体,在光源波长λ=532nm曝光下,测得含α的感光体达到饱和电位的时间45s、半衰曝光量5.7μJ/cm2、残余电位22V等数据.测得含β的感光体达到饱和电位的时间49s、半衰曝光量9.9μJ/cm2、残余电位22V等性能数值. 相似文献