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A series of ethyl(phenyl) 6-amino-2,3,6-trideoxy--D-glucopyranosides (amino=piperidino (Pip), pyrrolidino (Pyr), azetidino (Az), Bu2N) have been prepared from tri-O-acetyl-D-glucal to obtain catalysts for asymmetric synthesis and the starting compounds for the syntheses of other bidentate ligands.Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 45–52, January, 2000.  相似文献   
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Chiral 2-oxazolines are valuable building blocks and famous ligands for asymmetric catalysis. The most common synthesis involves the reaction of an amino alcohol with a carboxylic acid. In this paper, an efficient synthesis of 2-oxazolines has been achieved via the stereospecific isomerization of 3-amido-2-phenyl azetidines. The reactions were studied in the presence of both Brønsted and Lewis acids, and Cu(OTf)2 was found to be the most effective.  相似文献   
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Reactions of nucleophilic active phosphacumulenes with iso(thio)cyanate compounds were performed. The reaction products depend on the nature of the reagent, substrate and the condition of the reaction used. New heterocyclic 4-membered or 6-membered sulfur and nitrogen compounds such as phosphoranylidene thietane, azetidine and thiazinane were obtained. On the other hand, the stable phosphonium ylides with the iso(thio)cyanate afforded phosphoranylidene thiocarbamoyl derivatives. Possible reaction mechanisms are considered and the structural assignments are based on compatible analytical and spectroscopic data.  相似文献   
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1-二苯甲基-3-羟基氮杂环丁烷(1)经过对甲苯磺酰氯取代、叠氮化及还原反应合成了药物中间体--1-二苯甲基-3-氨基氮杂环丁烷(4);1经过氧化、氰基化与还原反应合成了1-二苯甲基-3-羟基-3-氨甲基氮杂环丁烷(8).4和8的结构经1H NMR表征.  相似文献   
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Photocycloreversion plays a central role in the study of the repair of DNA lesions, reverting them into the original pyrimidine nucleobases. Particularly, among the proposed mechanisms for the repair of DNA (6-4) photoproducts by photolyases, it has been suggested that it takes place through an intermediate characterized by a four-membered heterocyclic oxetane or azetidine ring, whose opening requires the reduction of the fused nucleobases. The specific role of this electron transfer step and its impact on the ring opening energetics remain to be understood. These processes are studied herein by means of quantum-chemical calculations on the two azetidine stereoisomers obtained from photocycloaddition between 6-azauracil and cyclohexene. First, we analyze the efficiency of the electron-transfer processes by computing the redox properties of the azetidine isomers as well as those of a series of aromatic photosensitizers acting as photoreductants and photo-oxidants. We find certain stereodifferentiation favoring oxidation of the cis-isomer, in agreement with previous experimental data. Second, we determine the reaction profiles of the ring-opening mechanism of the cationic, neutral, and anionic systems and assess their feasibility based on their energy barrier heights and the stability of the reactants and products. Results show that oxidation largely decreases the ring-opening energy barrier for both stereoisomers, even though the process is forecast as too slow to be competitive. Conversely, one-electron reduction dramatically facilitates the ring opening of the azetidine heterocycle. Considering the overall quantum-chemistry findings, N,N-dimethylaniline is proposed as an efficient photosensitizer to trigger the photoinduced cycloreversion of the DNA lesion model.  相似文献   
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以3-羟基氮杂环丁烷盐酸盐为原料,经取代、官能团转化制得3-氨基氮杂环丁烷化合物(3); 3经衍生化合成了10个3-氨基氮杂环丁烷衍生物(4a~4j),其中4f~4j为新化合物,其结构经1H NMR, 13C NMR和HR-MS(ESI-TOF)表征。采用MTT法初步测试了化合物的体外抗肿瘤活性。结果表明:4h对A549表现出较强的细胞毒活性(IC50=8.06 μmol·L-1)。  相似文献   
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符志成  许家喜 《化学进展》2018,30(8):1047-1066
氮杂环丁烷类化合物是一类重要的饱和四元含氮杂环化合物,不仅是有机合成中的重要原料、中间体及手性助剂或催化剂,也是氨基酸、生物碱及其天然和合成生物活性或药物活性化合物等分子结构中的重要活性单元。因此,发展氮杂环丁烷结构的合成方法非常重要。本文综述了氮杂环丁烷类化合物合成的发展,着重综述了近十年来该类化合物合成方法的进展,主要包括形成C-N键成环、形成C-C键成环、胺催化的亚胺和丙二烯甲酸酯环加成、亚胺和烯烃的光环加成、缩环扩环重排和氮杂环丁-2-酮(β-内酰胺)还原等方法构建氮杂环丁烷结构的新成果。  相似文献   
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