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1.
含硫杂环化合物广泛存在于天然产物、香料和药物分子之中,具有特殊的气味以及重要的生物活性,有着广泛的用途。这类化合物也是有机合成中一类非常重要的中间体。因此,含硫杂环化合物的合成研究备受关注。本文阐述了近几年来含硫杂环化合物的合成研究进展,对其相关性能进行了评价,并对该领域的发展前景进行了展望。  相似文献   

2.
醇氧化后生成的羰基化合物可以与胺形成亚胺中间体,再发生后续的环化反应,因此醇的氧化反应已被广泛地用于氮杂环化合物的合成.根据长期以来的研究经验,从不同类型氮杂环化合物产物出发,对过渡金属催化醇的氧化反应在合成氮杂环化合物中的应用进行了分类和综述,其中着重介绍了过渡金属催化醇的需氧和脱氢氧化在合成氮杂环化合物中的应用进展.  相似文献   

3.
研究了2,3-二氯-1,4-苯醌和二硫代草酰胺的反应,合成了三个具有平面型结构的含硫萘醌杂环化合物,该类杂环化物可以作为分子内电荷转移复合物的给体或是其它有机电导和有机光导材料的合成原料,所合成的化合物,经过熔点测定,元素分析和红外光谱分析确证了它们的结构。此外,本文还探讨了该类化合物的合成机理和影响合成反应的条件。  相似文献   

4.
吡唑并[1,5-α]吡啶衍生物的合成及其生物活性   总被引:2,自引:1,他引:1  
杂环化合物的发展将会使农药进入到一个超高效、无公害的绿色农药时代,杂环化合物已成为新农药发展的主流.在杂环化合物的发展过程中,含氮杂环最为重要.吡唑并吡啶化合物是一类非常重要的稠杂环,由于其特定的生理活性以及和吲哚、氮杂吲哚等在结构上的类似性,近来引起了人们广泛的研究兴趣.本文主要介绍吡唑并[1,5-α]吡啶类化合物的合成及其生物活性.  相似文献   

5.
由于氟原子赋予的特殊性能,含氟杂环化合物在医药、农药及特种功能材料等研究领域受到广泛关注.综述近年来本研究团队常用的一些新颖含氟砌块如含氟酮酸酯、含氟亚胺酰卤等的设计合成及其在含氟杂环化合物合成中的应用进展.  相似文献   

6.
噻吩并吡啶化合物具有广泛的生物活性,是一类非常重要的稠杂环.噻吩并吡啶化合物的合成方法从反应原料不同来区分,可分为以吡啶环为母环或以噻吩环为母环两种情形.该文主要综述噻吩并[3,2-b]吡啶、噻吩并[2,3-c]吡啶和噻吩并[3,2-c]吡啶等类型稠杂环衍生物的合成方法及其应用研究进展.  相似文献   

7.
杂环烯酮缩胺是一类用途广泛的合成子,常被用来合成一些用常规方法不易合成的稠杂环化合物.为了进一步研究杂环烯酮缩胺的结构对其反应性能的影响,以1,3-环己二酮为原料,经过碱化﹑加成﹑烷基化3步反应制备了烯酮缩二硫醚,再分别与乙二胺﹑丙二胺反应,得到了一类新型的环状杂环烯酮缩胺.  相似文献   

8.
对微波技术在合成六元杂环化合物中的应用作了概述,主要论及:1)含氧六元杂环化合物;2)含氮六元杂环化合物.  相似文献   

9.
苯并氮杂环化合物以其特殊的结构特点和广泛的生理及药理活性而备受关注,也是医药、化学品及功能化材料的基本原料或关键中间体,因此其绿色合成方法的研究是有机化学及药学领域的研究热点之一.苯并五元、六元、七元氮杂环化合物通常是由邻氨基苯酚(硫酚、二胺)与不同结构的羰基化合物反应制得,本文中,笔者阐述了近年来苯并五元、六元、七元氮杂环化合物的绿色合成方法的研究进展,归纳、整理、总结各类反应的特点和优势,并展望了其合成及应用的前景.  相似文献   

10.
正J Am Chem Soc 2016,138,13830-13833小分子含氮杂环化合物广泛存在于具有生物活性的化合物中.此外,含有N—H键的烯丙基内酰胺是一类非常有用的合成子及生物活性分子骨架.合成该类化合物的方法主要有过渡金属催化的伯酰胺对烯烃的环化反应和氮杂Wacker反应等.但以  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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