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以十一碳烯醇和碘戊烷为原料,经过苯甲酰基保护、9-硼双环[3.3.1]-壬烷(9-BBN)硼氢化后氧化、氯铬酸吡啶盐(PCC)氧化、Wittig反应、脱苯甲酰基五步反应得到顺-11-十六碳烯-1-醇(Z11-16:OH),五步反应总收率53%.顺-11-十六碳烯-1-醇经PCC氧化或Ac2O乙酰化分别得到顺-11-十六碳烯-1-醛(Z11-16:Ald)、顺-11-十六碳烯-1-醇乙酸酯(Z11-16:Ac),目标化合物及主要中间体结构经NMR,IR和MS确证.合成方法路线短,操作简便,收率较文献中的方法有较大提高. 相似文献
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研究了一系列结构新颖的具有除草活性的大环内酯衍生物的定量构效关系(QSAR). 构建的比较分子力场分析(CoMFA)、比较分子近似指数分析(CoMSIA)和全息定量构效关系(HQSAR)分子模型的交叉验证系数r2cv均大于0.5, 非交叉验证系数r2都超过0.8, 表明获取的QSAR模型具有可信的预测能力. 对CoMFA、CoMSIA模型的三维(3D)等势图分析, 发现除了立体场和静电场外, 疏水场和氢键受体场也是影响大环内酯类化合物除草活性的重要因素. 构建的HQSAR模型的原子贡献图提示的结构改造信息与三维QSAR的结果基本一致. 利用CoMFA、CoMSIA模型提供的信息,对目前已合成的活性最高化合物B1-3进行分子结构改造, 预测结果发现部分化合物可能具有更好的除草活性. 相似文献
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2011年11月29日,我们敬爱的导师张滂院士与世长辞。噩耗传来,作为学生的我们悲痛万分。师恩难忘,谨以此文作为对先生的纪念,并表达我们对先生的感谢与怀念之情。张滂先生早年就读于西南联大,毕业后曾作为老一辈有机化学家吴学周先生的助手开展研究工作。1945年留学英国,先后就读于利兹大学和剑桥大学,1949年7月获得有机化学博士学位。据了解,张滂先生是第一位获得剑桥大学博士学位的中国人。张先生于新中国成立之际回国效力,投身于祖国的教育和科技事业,先后任教于燕京大学和北京大学。 相似文献
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Two symmetrical (10a, 10b) and three unsymmetrical carbodiimides (10c, 10d, 10e) were synthesiz-ed from tris(β-methoxymethyl)ethylamine (1), bis(methoxymethyl)methylamine (2), and tris(methox-ymethyl)methylamine (3). They are neutral and readily soluble in many organic solvents including pe-troleum ether and possess sufficient solubilities in water except 10a which is less soluble. Their relativeabilities as condensing agent in the formation of peptide bonds were tested preliminarily by couplingphthalyl glycine and glycine ethyl ester in chloroform as well as in water and can be related to the stericeffects exerted by methoxymethyl-substituted alkyl residues with the order: tertiary>primary>secondary.1,3-Bis[bis(methoxymethyl)methyl] carbodiimide (10b) is promising as an all-soluble condensing agentfor the formation of peptide linkage and by its ready availability. 相似文献
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N—取代—α—氧代环十二烷基磺酰胺的合成及其杀菌活性 总被引:13,自引:0,他引:13
以易得的环十二酮为原料,由磺化获得中间体α-氧代环十二烷基磺酸后,再经生成磺酰氯和胺化反应合成了一系列N-取代-α-氧代环十二烷基磺酰胺。生物活性测定结果表明,它们对小麦赤霉病菌的生长具有抑制作用,其中活性最高的是氮上取代有一氯苯基的化合物,通过构象分析讨论了它们的结构-活性关系。 相似文献
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Ten α,α,α′-trisubstituted cyclododecanones were synthesized and characterized by elemental analyses, infrared, 1^H NMR and 13^C NMR spectra, and X-ray diffraction. NMR data could not give conformational information clearly, but some of their ring skeleton conformations of cyclododecanone moiety were showed to remain the unchanged [3333]-2-one conformation with little distortion, while the others were changed to the [3324]-2-one conformation in their crystal structures. These are consistent with the results of molecular mechanics calculation with Sybyl 6.9 software and Tripos force field, and semi-empirical quantum calculation with AM 1 method in Gaussian 98 software. Two geminal substituting groups are located at α-corner carbon atom, and the third group is at α-side-exo carbon atom in both conformations. Both [3333]-2-one and [3324]-2-one conformations are present in a dynamic equilibrium in the solution, but only one preferred conformation exists in the crystal solid. 相似文献