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1.
有机硅化合物不仅是十分有用的功能分子,而且是非常重要的有机合成中间体,在一定条件下通过适当的化学方法,可以转化为很多其它有用的功能性化合物.到目前为止,已经陆续发展了各种过渡金属参与的催化方法来制备有机硅化合物,其中铜催化不饱和化合物的硅加成反应是一种重要的合成有机硅化合物的方法.从不饱和化合物的种类出发,主要涉及α,β-不饱和化合物、亚胺、Morita-Baylis-Hillman(MBH)醇类化合物、对苯醌甲基化合物、α,β-不饱和炔羰化合物以及α,β-不饱和砜类化合物,综述了近几年在铜催化作用下这些不饱和化合物通过硅加成反应合成有机硅化合物的最新研究进展,有利于加深对铜催化硅加成反应的理解.  相似文献   

2.
钟平 《有机化学》2004,24(4):374-379
烯基锆化合物及硒基烯基锆化合物、锡基烯基锆化合物、磺酰基烯基锆化合物、亚磺酰基烯基锆化合物、硅基烯基锆化合物等金属或杂原子取代的烯基锆化合物 ,可通过锆氢化反应高产率和高选择性地制得 .这些试剂可与各种亲电试剂反应立体选择性地合成二取代或三取代的烯烃化合物  相似文献   

3.
采用α-酸糖蛋白手性固定相(Chiral-AGP),固定流动相pH、流速,化合物样品浓度,考察酸性、碱性、中性手性化合物和21个氨基酸在α-酸糖蛋白手性柱上的拆分情况.应用高效液相色谱法,α-酸糖蛋白手性柱对上述手性样品拆分,一共有8个中性化合物、3个碱性化合物、6个酸性化合物和5个氨基酸得到手性对映分离.探讨了α-酸糖蛋白手性柱对酸性、中性、碱性样品的拆分能力并进行对比,结果证明α-酸糖蛋白手性柱拆分中性化合物和酸性化合物效果最好,拆分碱性化合物和氨基酸效果不好,为α-酸糖蛋白手性柱适合于拆分哪一类型的手性化合物提供参考.  相似文献   

4.
综合利用1H NMR、13C NMR、DEPT、COSY、HMQC和HMBC等NMR技术,对从黄草乌中分离提取的粗茎乌碱类化合物进行了结构解析,分析结果表明,该化合物含有乌头生物碱化合物母核,以及1个甲氧基苯基片段和1个乙酸基片段,并最终确证该化合物为粗茎乌碱Ⅰ.根据该化合物特有的刚性特征,利用ROESY实验并辅以1D-GOESY等实验手段完成了该化合物的相对空间结构的解析.  相似文献   

5.
以取代1,2,3-噻二唑为原料,合成了一系列未见文献报道的含有1,2,3-噻二唑、1,2,4-三唑的双杂环类硫苷化合物(6a~6d)。目标化合物的结构经过1H NMR、13C NMR和IR等技术手段表征确认,重点对比了含西弗碱化合物5与还原后化合物6的抗菌活性变化。体外抑菌测试结果显示,所有化合物对大肠杆菌、金黄色葡萄球菌和白色念珠菌均表现出较好的抑制活性,含有西弗碱化合物5的抗菌活性普遍优于还原后化合物6,其中化合物5d表现出很强的抗菌活性,其最小抑菌浓度优于市售抗菌药氟康唑;所有目标化合物对白色念珠菌的最小抑菌浓度均小于或等于32 mg/L。  相似文献   

6.
含氧、氮、硫杂螺环结构的光致变色化合物研究进展   总被引:1,自引:0,他引:1  
魏荣宝  张大为  梁娅  刘博 《有机化学》2008,28(8):1366-1378
有机螺环光致变色化合物具有较好的化学稳定性、光敏性和抗光疲劳性, 可应用于光过滤器及光学记录存储. 为了获得性能优良的螺环光致变色化合物, 新的设计合成一直是该领域研究的热点. 总结了对含氧、氮、硫杂螺环结构的光致变色化合物的研究进展, 描述了螺环化合物的结构特征和部分化合物的合成过程, 展望了螺环光致变色化合物的发展前景.  相似文献   

7.
N-取代苯基-卤代邻羟基苄胺的合成、表征及抑菌活性   总被引:2,自引:0,他引:2  
通过卤代水杨醛与取代芳胺缩合、NaBH4还原, 合成了15种N-取代苯基-卤代邻羟基苄胺化合物, 其中14种未见报道. 化合物的结构经IR, 1H NMR, MS与元素分析表征确证. 抑菌测试表明, 在质量浓度为0.05%时, 化合物对白色念珠菌的抑菌率高达100%, 具有强抑菌活性, 对金黄色葡萄球菌、大肠杆菌有一定的抑菌活性. 该类化合物对不同菌株的抑菌活性具有明显的选择性和特异性, 是一类极具潜力的抗真菌化合物. 构效分析表明, 胺基苯环上取代基的类型对化合物抑菌活性有重要影响, 引入F, Cl等卤原子, 能显著增强化合物的抑菌活性, 而引入NO2, OCH3等强吸、供电基团, 能显著降低其抑菌活性; 邻羟基苯环上引入卤原子的类型和数量对化合物抑菌活性有一定影响, 5-溴代化合物比5-氯代化合物、3,5-二溴代化合物对大肠杆菌的抑菌活性更高.  相似文献   

8.
聂永  苗金玲 《大学化学》2013,28(4):39-43
按照狭义的分类方法,对含有硼碳键的有机硼化合物的分类进行探讨。根据结构类型,有机硼化合物可以分为烃基硼烷、烃基硼酸(酯)、烃基硼烷路易斯碱加合物和离子型有机硼化合物、有机硼杂环及其金属配合物、碳硼烷簇合物及其金属化合物等类型。对不同类型的有机硼化合物的命名进行了归纳,并给出了一些代表性化合物的英汉对照名称。  相似文献   

9.
合成了一系列稳定高效的新型碳糖苷类熊果苷类似物,其中10个化合物未见文献报道. 化合物结构通过核磁及质谱确证. 初步生物活性测试结果表明,目标化合物具有良好的酪氨酸酶抑制活性,其中化合物13、14、15、16、19的活性接近或优于天然熊果苷.  相似文献   

10.
气相色谱-质谱法定性定量分析烟叶挥发性香气成分   总被引:1,自引:0,他引:1  
本文研究了质谱去卷积算法在化合物结构定性中的作用。采用质谱去卷积和质谱库检索、色谱保留指数、标样定性等相结合的方法从烟叶样品中鉴定出118个挥发性香气成分,其中57个醛酮类化合物、23个醇类化合物、16个含氮类化合物、7个有机酸类化合物、15个其它化合物。采用定量离子进行定量,有效降低了重叠峰干扰,使色谱积分结果更为真实准确。对所鉴定的化合物进行重复性考察,结果表明有60.2%的化合物的相对标准偏差(RSD)小于20%,80.5%的化合物的RSD小于30%。线性响应考察结果表明有80个化合物的线性相关系数(R2)在0.90以上,适合于定性或定量分析。  相似文献   

11.
The structural principles known to date serving as the basis for the design of heterocyclic compounds with anomalously high basicity (superbasicity) are reviewed. A general classification is given for such superbases as proton sponges, compounds that are similar to proton sponges but are not sponges (proton-sponge-like), and proton traps.  相似文献   

12.
Marine sponges are a rich source of biologically active secondary metabolites with novel chemical structures. Eighty four anti-inflammatory compounds have been isolated from marine sponges. This is the first comprehensive review presenting the structures and anti-inflammatory activities of marine sponge metabolites. (100 references).  相似文献   

13.
A test procedure for evaluating the effect of adding commercial liquid hand dishwashing detergents to kitchen sponges to control microbial growth is described. Claims for this type of application are being made on dishwashing detergents throughout the world. In this evaluation, commercially available kitchen sponges were stripped of antimicrobial compounds. Sponges were then inoculated with a pool of 7 microorganisms which consisted of gram positives, gram negatives, and yeast. Inoculated sponges were treated with the detergent as recommended by the manufacturer and allowed to incubate for 16 h at ambient temperature. Surviving microorganisms were then quantitated using either the spiral or pour plate method. Tests were run using both clean sponges and sponges soiled with 0.5% nonfat dry milk (NFDM). Untreated sponges showed stasis or slightly increased bacterial populations after the incubation period in the absence of NFDM. Significant increases of up to 3 log cfu/mL were observed for untreated sponges when soiled with NFDM. Statistically significant reductions were observed for clean sponges (99.8-99.9998%) and sponges soiled with NFDM (87.6-99.9%) when detergents making "antibacterial sponge" claims were added to the inoculated sponges. Statistically significant differences between detergents making "antibacterial sponge" claims were also observed.  相似文献   

14.
Cold-water marine natural products   总被引:2,自引:0,他引:2  
Marine natural products isolated from organisms collected from cold-water habitats are described. Emphasis is on bioactive compounds from tunicates, sponges, microbes, bryozoans, corals, algae, molluscs and echinoderms. Synthetic studies of several important classes of cold-water compounds are highlighted.  相似文献   

15.
海洋溴吡咯生物碱的研究进展   总被引:4,自引:0,他引:4  
刘家峰  郭松坡  姜标 《有机化学》2005,25(7):788-799
大量的溴吡咯生物碱从海绵中得到分离, 并表现出良好的生理活性. 这类化合物因其结构的新颖性、多样性、以及良好的生理活性而成为合成化学家关注的焦点. 综述了近年来海洋溴吡咯生物碱的分离和合成进展.  相似文献   

16.
Four species of marine sponges (Phylum Porifera, Order Dictyoceratida), which contain the filamentous cyanobacterial symbiont Oscillatoria spongeliae, were collected from four locations in Palau. The halogenated natural products associated with the symbiont were characterized from each sample, revealing that each species contained either chlorinated peptides, brominated diphenyl ethers, or no halogenated compounds. Analysis of the host sponges and the symbionts indicated that each species of sponge contained a distinct strain of morphologically similar cyanobacteria. Although cospeciation may be present in this group, we have identified that at least one host switching event has occurred in this symbiosis. Only the strain of O. spongeliae in the sponge containing the chlorinated compounds possessed genes involved in the biosynthesis of chlorinated leucine precursors, indicating that the chemical variation observed in these animals has a genetic foundation.  相似文献   

17.
The nudibranch Cadlina luteomarginata from San Diego, California, concentrates selected metabolites from the sponges that constitute its diet. Gut analyses revealed that C. leutomarginata consumes at least ten sponges although Axinella sp. and Myxilla incrustans are most frequently eaten. Field observations and analysis of metabolites suggest that keratose sponges Leiosella idia (=Spongia idia) and Dysidea amblia are also consumed. Three novel compounds, the furan 20, the isonitrile 23 and the isothiocyanate 24 were identified by analysis of spectral data. The secondary metabolites of C. leuteomarginata were found only in the dorsum, which is exposed to potential predators. Five metabolites of C. luteomarginata were screened for antifeedant activity against fish and all showed some activity at 10–100 μ/mg in food pellets.  相似文献   

18.
<正>Hyrtiosulawesine was isolated from Indonesian specimens of the marine sponges Hyrtios erectus and H.reticulatu in 2002.We report here the first total synthesis of hyrtiosulawesine using an efficient and convenient synthetic strategy which could be widely used in the synthesis of otherβ-carboline compounds.All structures of new compounds were confirmed by ~1H NMR,~(13)C NMR and HRMS.  相似文献   

19.
An overview of the chemistry and microbiology of calcareous sponges (Calcispongiae) is provided, highlighting the potential of these sessile filter-feeding marine invertebrates and their associated bacteria for the discovery of new bioactive natural products. 103 compounds are presented and 116 references cited.  相似文献   

20.
龙康侯  林永成 《有机化学》1985,5(5):369-375
八十年代以来,海洋天然有机化学仍然继续发展,大量新的化合物,尤其是具有生理活性的化合物不断出现,海洋天然物的生物合成和人工合成研究也有新的进展。在海洋生物中,研究得最多的是海藻和海绵,其次便是珊瑚。  相似文献   

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