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91.
麻锦彪  吴厚铭 《化学进展》1999,11(3):265-274
由于许多药物通过和生物体内的大分子(如蛋白质和核酸) 的选择性结合发挥效用, 因此快速、有效地发现靶分子的高亲和性配体成为各种药物发现方法的首要目标。在现代生物技术和NMR 技术高度发展的基础上产生的一种发现生物大分子高亲和性配体的新方法--SAR-by-NMR, 由于采用NMR 技术可以综合多种药物设计方法的优势, 能够在短时间内得到先导化合物, 从而大大加快了药物发现的速度并能节省大量的费用。本文介绍了SAR-by-NMR 发现高亲和性配体的基本原理、特点及其在药物发现中的应用。  相似文献   
92.
《中国化学》2018,36(2):129-133
The sulfoximine group has been evaluated as a pharmacophore. Introducing the sulfoximine structure into medicinal compounds as exciting motifs has brought opportunities in drug discovery. In order to develop new ryanodine receptor (RyR) modulators, a series of phthalamides containing sulfoximine derivatives were designed, synthesized, and evaluated against oriental armyworm and diamondback moth for their insecticidal activities. These studies helped to elucidate the electronic and structural requirements around the sulfoximine motif for insecticidal activity. All new structures were synthesized and characterized by 1H NMR, 13C NMR, HRMS and bioassay and a preliminary structure − activity relationship (SAR) was discussed. The biological assessment indicated that most title compounds showed good to excellent larvicidal activities. Compounds Ia , Ie , and If gave excellent insecticidal activity against oriental armyworm, which showed 100% larvicidal activity at 0.5 mg/L. All compounds showed 100% larvicidal activity at 0.1 mg/L against diamondback moth. In particular, the larvicidal activities of Ie , If , and Ih at 0.0001 mg/L were 50%, 20%, and 40%, respectively, reaching an activity as high as that of the commercial flubendiamide (40%, 0.0001 mg/L). Therefore, Ia , Ie , If and Ih could be considered as new lead structures for the development of new ryanodine receptor (RyR) modulators.  相似文献   
93.
茶酚-氧位-甲基转移(COMT)酶抑制剂在治疗帕金森病中起到重要作用.通过对现有COMT酶抑制剂托卡朋和恩托卡朋结构与活性关系分析,推断含有儿茶酚结构的香豆素类化合物可能具有潜在的COMT酶抑制活性,因此设计合成了一类新型的6,7-二氧代-4-芳胺香豆素,通过理论计算,研究了此类化合物对COMT酶抑制活性.结果表明,设计的10种6,7-二氧代-4-芳胺香豆素与COMT酶的对接效果均较好,其中具有甲氧基乙基保护的儿茶酚结构化合物6,7-二[2-(甲氧基)乙氧]-4-(苯胺)香豆素(6b4)和6,7-二[2-(甲氧基)乙氧]-4-[(3-乙炔基)苯胺]香豆素(6b5)与COMT酶的对接效果尤为显著.  相似文献   
94.
Total synthesis of two cytotoxic natural products, nelumol A (1) and nelumal A (2), were carried out by two different paths. 4-O-Benzyl substitute analogues 26 and 27, as well as the 4-O-(2-methyl-butenyl) derivatives 29 and 30 were also synthesized for a SAR investigation. 1 and 2 were also measured on different tumor cell line.  相似文献   
95.
Cytotoxic compounds are crucial in the course of finding new anti-tumor leading compounds. Chen and his co-workers recently reported the isolation of sintenin 1 which possessed selective cytotoxicity against P-388 cells with an ED50 value of 0.21 μg/mL1. As to our knowledge, this kind of esters should have broader-spectrum of biological activity2,3. Furthermore, the structure of 1 is relatively similar to nelumol B-D, the sinapyl alcohol derivatives isolated from Ligularia nelumbifolia, wh…  相似文献   
96.
黄酮体化合物抗肿瘤活性的量子化学研究   总被引:9,自引:0,他引:9  
本文对黄酮类化合物抗肿瘤活性进行了量子化学研究。采用从头算方法计算了黄酮体化合物的电荷分布,并基于电荷分布提出了黄酮体化合物表现抗肿瘤活性时与受体作用的模型:A环与受体的负电荷中心结构,C环与受体的正电荷中心结合,其他部分通过氢键与受体发生作用,氢键在受体的作用中起到很大的作用。  相似文献   
97.
重点考察了反映分子整体性质的表面积及构象差异等结构因素对活性的影响,以活性PI_(50)值落于7.5751~3.0752之间的23个新合成的磺酰脲分子为研究对象,运用多元回归方法进行了研究,结果表明:反映分子表面积大小的AREA值及反映分子构象差异的d1、d2、d值明显地影响了此类磺酰脲农药分子的活性.  相似文献   
98.
4-氨基-5-吡啶-4-基-均三唑硫醇(1)在复合催化剂DMAP和TBAB作用下与对卤代苯甲酸经环缩合反应以高收率得到中间体6-(5-氯-3-甲基-1-取代苯基-1H-吡唑-4-基)-3-吡啶-3-基-均三唑并[3,4-b][1,3,4]噻二唑(2a2c), 接着苯环卤原子与取代哌嗪在聚乙二醇催化作用下发生亲核取代反应得到相应的哌嗪游离碱(3a3c). 其中, 单取代哌嗪游离碱3a与含功能基的卤代物缩合得到功能基取代的哌嗪衍生物(4a4g). 这些产生的游离碱与盐酸反应得到相应的水溶性盐酸盐. 所合成新化合物的结构经元素分析和光谱数据表征, 并评价了它们的体外抗菌活性及构效关系.  相似文献   
99.
An internal historical point of view is presented on the discovery and development of both methyl jasmonate and its saturated analogue Hedione®. A discussion of the synthetic approaches performed during the last decade, and structure? activity relationships of analogous structures are also presented.  相似文献   
100.
Complexes [Sb(2Ac4oClPh)Cl2] (1), [Sb(2Ac4oFPh)Cl2] (2), [Sb(2Ac4oNO2Ph)Cl2] (3), [Sb(2Bz4oClPh)Cl2] (4), [Sb(2Bz4oFPh)Cl2] (5) and [Sb(2Bz4oNO2Ph)Cl2] (6) were obtained with 2-acetylpyridine-N(4)-ortho-chlorophenyl thiosemicarbazone (H2Ac4oClPh) and its N(4)-ortho-fluor (H2Ac4oFPh) and N(4)-ortho-nitro (H2Ac4oNO2Ph) analogues, and with the corresponding 2-benzoylpyridine-derived thiosemicarbazones (H2Bz4oClPh, H2Bz4oFPh, H2Bz4oNO2Ph). The studied compounds are excellent inhibitors of Trypanosoma cruzi growth. H2Bz4oClPh and complexes (4) and (1) were the most trypanosomicidal.Upon coordination of H2Ac4oClPh to antimony(III) in 1, the therapeutic index (TI) goes from 10.58 to 14.35. However, the best values of TI were found for H2Bz4oClPh (TI = 1240) and H2Ac4oNO2Ph (TI = 773). Structure-activity relationship (SAR) studies did not allow the establishment of correlations between the anti-trypanosomal activity and physico-chemical parameters, but correlations were found between the cytotoxicities and physico-chemical properties.  相似文献   
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