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1.
《分析化学》2012,(11):1667
(ISBN 978-7-122-12700-6)该书全面收集了生物碱类、皂苷类、黄酮类、醌类、单萜类、倍半萜类、二萜类、三萜类、其它萜类、苯丙素类、甾体类、二苯乙烯类、环庚三烯酚酮和脑苷脂类、海洋天然产物类、氨基酸和糖类共17大类1万余种天然有机化合物的氢核磁共振谱数据。每一种化合物都给出了名称、分子式、结构式、~1H的化学位移和偶合常数数据,以及相应的参考文献。书后  相似文献   

2.
自菊科蒿属植物万年蒿(Artemisia Sacrorum Ledeb)地上部分首次分得三个贝壳杉烷型(Kauranetape)二萜类化合物,经理化常数测定及光谱分析(IR,’H-NMR,~(13)C-NMR,MS,二维核磁共振光谱)鉴定其结构分别为:3α,16α,17-三羟基贝壳杉烷[I],3α,16α-二羟基贝壳杉烷-17-0-β-D-葡萄糖甙[Ⅱ]和16α-羟基贝壳杉-3-酮-17-0-β-D-葡萄糖甙[Ⅲ]。其中[Ⅰ]为一新天然产物,[Ⅱ]为一未见报道的新化合物。通过对该三个化合物的~(13)C-NMR光谱分析,讨论了不同位置取代基对其~(13)C-NMR光谱化学位移的影响。  相似文献   

3.
《分析化学》2014,(1):82
本书全面介绍了天然产物的有机合成机理,并通过丰富的实例详细阐述了合成路线的设计技巧和艺术。分别介绍了天然产物有机合成的一些重要方法和基本策略;对天然产物合成中常见的近400个有机化学反应机理进行了系统归纳和简要描述;选取35个典型的具有重要生物活性的天然产物(包括生物碱、萜类、植物酚类和甾体等)实例,分别对它们进行了逆合成分析和合成路线解析。  相似文献   

4.
~(13)C-NMR是分析有机化合物碳链结构的有效手段,但对于某些化合物特别是聚合物,很难找到已知结构的标准谱图来对照确定其结构。近年来发表的饱和链烃~(13)C-NMR 化学位移计算公式因计算过程较繁,笔算很费时间。本文介绍的用 PC-1500袖珍计算机计算的方法,不仅能算出~(13)C-NMR 化学位移并能模拟~(13)C-NMR 谱图,快速、简便、直观,几分钟内即可  相似文献   

5.
《分析化学》2012,(11):1692
(ISBN 978-7-122-12695-5)本书是全面收集了生物碱类、萜类、皂、苷类、黄酮类、醌类、苯丙素类、甾体类、芳香族类、脂肪族类,木脂素、香豆素、氨基酸和糖类、海洋天然产物、抗生素等2万余种天然有机化合物的核磁共振碳谱数据,每一种化合物都给出了相应的名称、分子式、结构式、测试溶剂和碳的化学位移数据以及参考文献。书后还附有化合物中英文名称索引以及分子式  相似文献   

6.
三萜和甾体是由六个异戊二烯单元组成的一大类天然产物,具有复杂多样的化学结构和广泛的生物活性.真菌是三萜和甾体化合物发现的重要源泉,但与植物相比,目前从真菌中发现的三萜骨架类型仍然很少,仍有较大的研究空间.基因组挖掘已成为后基因组时代发现新颖天然产物的重要手段,其主要通过与相似功能基因的比较来发现新功能基因.随着高通量测序技术和生物信息技术的飞速发展,一些具有重要生物活性的真菌三萜或甾体的生物合成途径逐渐被阐明,这为利用基因组挖据手段从真菌中发现新颖三萜或甾体化合物奠定了基础.重点介绍近年来在真菌三萜或甾体生物合成方面的研究进展情况.  相似文献   

7.
计算机辅助有机化合物结构解析工作可粗分为数据库检索和人工智能解析两大类。本文通过子结构(本文中的子结构是以碳原子为中心的β层子结构,以下同)与~(13)C-NMR谱相关性研究,并建立~(13)C-NMR谱自动解析系统。首先,采用统计方法,由已知波谱数据寻求共振碳的β层环境结构与共振碳化学位移的对应范围,产生以碳为中心原子的β层子结构-~(13)C-NMR谱相关表。在解析未知化合物结构时,由未  相似文献   

8.
盐酸阿扎司琼(Azasetron hydrochloride)是一种高选择性,副作用低的5-HT_3受体拮抗剂。本研究通过文献调研发现目前已报道的合成路线存在着工艺复杂,污染大等问题。针对这些问题,本研究报道了一条更加简便,环保,有工业化潜力的路线,通过五步反应得到目标产物,其结构经~1H-NMR、~(13)C-NMR及MS确认,总收率67.5%。  相似文献   

9.
雌甾-11-酮化合物是合成具有强效抗生育活性11-烃基取代在甾体化合物的关键中间体。本文对13β-乙基-3-甲氧基-甾-1,3,5(10), 9(11)-四烯-17β-醇的硼氢化-铬酸氧化反应进行研究, 结果发现产物比较复杂, 在温和条件下, 主要产物为13β-乙基-3-甲氧基-甾-1,3,5(10)-三烯-17-酮-112-硼酸, 增加氧化剂用量, 延长反应时间则得到11,17-二酮。  相似文献   

10.
本文系统介绍了结构解析专家系统ESESOC.I.的研制过程。该系统能够综合利用IR,~1H-NMR,~(13)C-NMR对含有C,H,O的有机化合物结构进行自动解析。  相似文献   

11.
通过几个应用例子 ,说明了作者建立的Sadtler标准碳谱检索系统是有机物定性分析和结构指定的必备工具之一  相似文献   

12.
Thermolysis of steroidal 5α, 8α- peroxides of type 3a-d generates as major products the corresponding diseco compounds containing a 14-membered ring instead of the standard A-B-C-ring skeleton. Depending on the reaction conditions, either the primary products of type 9 or the α, β-unsaturated ketones of type 4 , formed by subsequent elimination of AcOH, are isolated. The latter, configurationally uniform compounds undergo epoxidation of the C(9)=C(10) bond followed by a Baeyer-Villiger oxidation to give, as final products, the 15-membered cyclic epoxyenol lactones of type 20 and 21 . The structures of the various products were determined by 1H- and 13C-NMR spectroscopy. The conformations of the 14- and 15-membered rings were established by X-ray structure analyses of 7 and 21a . A reaction mechanism for the above transformations is discussed.  相似文献   

13.
A new steroidal saponin was isolated from the leaves of Agave attenuata. Its structure was established as (3beta,beta,25S)-spirostan-3-yl O-beta-D-glucopyranosyl-(1 --> 2)-beta-D-glucopyranosyl-(1 --> 2)-O-[beta-D-glucopyranosyl-(1 --> 3)]-beta-D-glucopyranosyl-(1 --> 4)-beta-D-galactopyranoside. The structural identification was performed using detailed analyses of 1H- and 13C-NMR spectra including 2D NMR spectroscopic techniques (COSY, HETCOR, and COLOC) and chemical conversions. The hemolytic activity of the steroidal saponin was evaluated using an in vitro assay.  相似文献   

14.
A new steroidal saponin was isolated from the leaves of Agave shrevei. Its structure was established as 3-[O-beta-D-glucopyranosyl-(1-->2)-O-[O-beta-D-glucopyranosyl-(1-->4)-O-[O-beta-D-glucopyranosyl-(1-->6)]-O-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranosyl)-oxy]-(3beta,5alpha,25R)-spirostane. The structural identification was performed using detailed analyses of 1H- and 13C-NMR spectra including 2D NMR spectroscopic techniques (COSY, HETCOR, HMBC, and HMQC) and chemical conversions. The haemolytic activity of the steroidal saponin was evaluated using an in vitro assay.  相似文献   

15.
The configuration of a computerized information system for organic chemistry is outlined. Data banks for infrared, 13C-NMR, mass and x-ray diffraction spectra are accessed individually or from a central structure-handling and search system. Other facilities include a Chinese chemical documentation system, accessible in English or Chinese, and data analysis by multivariate techniques.  相似文献   

16.
端羟基聚丁二烯(HTPB)的~(13)C-NMR研究   总被引:2,自引:0,他引:2  
<正> 以过氧化氢催化丁二烯聚合而得到的端羟基聚丁二烯(HTPB)在工业上具有广泛的用途,当它们发生交联时,即能形成结构体,用作推进剂、涂料和其它材料的基体,HTPB的质量对其最终产物的力学性能起着决定性的作用。然而人们已经发现,在某些情况下,使用相同牌号的HTPB,甚至用常规的分析方法进行鉴定认为是相同的HTPB,其交联体  相似文献   

17.
The expert system CARBON is built around a knowledge base consisting of spectra/structure correlations, tables of data, mathematical formulae and graph-theory procedures and on a data base of 2500 assigned 13C-NMR spectra. The built-in knowledge enables the user to obtain suggestions for solutions to problems of different types arising in 13C-NMR spectroscopy. Use of the system is facilitated by appropriate command files, large on-line help files, and user-friendly dialogue. The system can be used with spectrometries other than 13C-NMR and in other fields concerned with correlations between chemical structures and properties.  相似文献   

18.
ComputerHandlingofChemicalandBiologicalDataofTraditionalChineseMedicinesCHEChun-taoa**,PaulR.CarlieraandOpheliaC.W.Leeb(aDepa...  相似文献   

19.
Accurate, practical prediction of 13C NMR chemical shifts has been achieved with a new system, CAST/CNMR, taking account of stereochemistry. The CAST/CNMR system has solved the critical problem of the accurate distinction of differences and similarities in stereochemical structures around a specific carbon, which has not yet been achieved by any other database-oriented system for prediction of 13C NMR chemical shifts. CAST/CNMR uses a three-dimensional structural database together with a 13C NMR spectral database. Absolute/relative configurational and conformational structural information are described by the CAST (CAnonical-representation of STereochemistry) coding method. This paper provides an overview of the CAST/CNMR system, and describes its application to two natural products as examples.  相似文献   

20.
Diarylheptanoids, natural products with a 1,7-diphenylheptane structural skeleton, are mainly distributed in the roots, rhizomes and bark of Alpinia, Zingiber, Curcuma and Alnus species. They have become of interest in natural product research over the past twenty years because of their remarkable anti-cancer, anti-emetic, estrogenic, anti-microbial and anti-oxidant activity. This paper compiles all 307 naturally occurring diarylheptanoids from 46 plants as reported in 137 references with their distributions, physiological activities and 13C-NMR spectral data.  相似文献   

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