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以促性腺激素释放激素类似物(GnRHa)为靶向配体, 以紫杉醇为抗癌因子, 分别以硫醚键和二硫键为连接臂, 设计合成了2个靶向抗肿瘤缀合物. 研究了缀合物的肿瘤细胞增殖抑制活性和GnRH受体结合活性, 结果表明, 2个缀合物均具有较强的抗肿瘤活性和GnRH受体亲和力; 另外, 血浆稳定性实验结果显示, 以硫醚键偶联的缀合物1在血浆中孵育24 h, 原型保留仍在50%以上, 具有较高的稳定性. 相似文献
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芳基吡咯类小分子化合物NB-2衍生物(Noc或Npc)与衍生于C34中的靶标特异性多肽P26所形成的缀合物具有低纳摩尔水平的融合抑制活性.本文通过不同长度或不同柔性的连接臂将Noc或Npc与衍生于C34的靶标特异性多肽P27缀合,探讨了C34中a位残基I635和连接臂对缀合物活性的影响.人体免疫缺陷病毒1型(HIV-1)Env介导的细胞-细胞融合实验结果表明,多肽与小分子之间产生了强的协同作用. 相似文献
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鹅去氧胆酸是天然的初级胆汁酸,是鸡、鸭和鹅等家禽胆汁中的主要有机成分,具有杀菌、抗炎和溶解胆结石等作用,是临床上治疗胆固醇结石的药物之一,也是合成临床上治疗胆结石疾病用量最大的药物熊去氧胆酸的原料。鹅去氧胆酸在医药方面的应用价值促使其制备方法逐步完善。近年来,关于鹅去氧胆酸衍生物的研究越来越多,相关研究也延伸到生物医药、分子识别和功能材料等多个领域,尤其在生物医药领域,鹅去氧胆酸衍生物显示出广阔的应用前景。本文系统地综述了鹅去氧胆酸的提取、合成与化学修饰方法,以及鹅去氧胆酸衍生物的合成、性质及应用,并展望了其发展前景。 相似文献
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《有机化学》2016,(11)
蛋白酪氨酸磷酸酯酶1B(PTP1B)是体内胰岛素信号通路的负调控因子,被视为治疗糖尿病的潜在靶标.甾体类天然产物石胆酸3(LCA)具有较好的PTP1B抑制活性.为了提供石胆酸衍生合成多样性的基本骨架,并探讨甾环上特定位点(3,4,5,6及23位)取代基及其构型与PTP1B抑制活性的关系,设计并合成了一组石胆酸类似物.PTP1B抑制活性测试结果显示,3β-羟基胆烷-4-烯酸(17)和4,4-二甲基-3β-羟基-5-烯-胆烷酸(19)对PTP1B的抑制活性均比石胆酸有所提高,分别达到(8.50±1.21)和(6.27±1.03)μmol·L-1.此外,通过计算机模拟对接阐明了两个化合物与酶的可能结合方式.为进一步研究PTP1B抑制剂提供了新的骨架化合物及有价值的构效关系信息. 相似文献
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N-4-羟基苯基维甲酰胺与呋咱氮氧化物偶联物的合成及抗肿瘤活性研究 总被引:3,自引:0,他引:3
为了寻找治疗乳腺癌的药物, 将N-4-羟基苯基维甲酰胺(4-HPR)以乙酸为连接基团通过酯键或酰胺键与NO供体呋咱氮氧化物缀合, 合成了NO供体型维甲酸类化合物, 共11个新的目标化合物, 其结构经IR, MS, 1H NMR和元素分析表征, 总收率为8.8%~12.9%. 对目标物进行体外抗乳腺癌活性测试, 结果表明, 所有目标物均具有不同程度的抗肿瘤活性, 其中8g抗肿瘤活性和对照药阿霉素相当. 相似文献
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Novel fluconazole/bile acid conjugates were designed and their regioselective synthesis was achieved in very high yield via Cu(I) catalyzed intermolecular 1,3-dipolar cycloaddition. These new molecules showed good antifungal activity against Candida species. 相似文献
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本文综述近几年来胆甾酸缀合物的生物及生理学功能研究概况。主要包括胆甾酸天然缀合物模拟的化学合成,新的生物活性的探索;胆甾酸的表面两性结构在抗生素、离子通道、分子载体方面的应用;利用其生理循环途径设计、化学合成胆甾酸缀合物以及空间结构的利用研究。 相似文献
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Cholic acid (or 3a,7a,12a-trihydoxyl-5a-cholan-24-oic acid) and lithocholic acid (or 3a-hydroxyl-5a-cholanic-24-oic acid) are commonly occurring bile acids synthesized from cholesterol in the liver in mammals. They all possess a steroid skeleton containing four rings, three with six carbons and one with five carbons. The transformation of cholesterol to cholic acid results in two major structural changes that affect the steroid skeleton. The first is the hydrogenation of the double bond between C5 and C6 and the second is a conformational flip of ring A from the 5a-position to the 5a-position. In addition, one or more hydroxyl groups are added to the steroid skeleton. Outside of the ring system, C24 is converted from a saturated alkyl to a carboxylic acid group.Side chain polymers based on cholesterol moiety have been made as reported in the literature.Since bile acids and cholesterol are all in the family of steroid molecules, it is of interest to investigate whether bile acids may also act as mesogenic groups.Therefore, flexible spacer groups with 10 carbons are introduced between bile acid skeleton and the poymerizable double bonds. The monomers and polymers are compared with cholesterol and dihydrocholesterol monomers and polymers with the same spacers. Dihydrocholesterol is chosen to investigate the influence of the double bond in the formation of LC, given that both cholesterol and dihydrocholesterol have a planar structure but there is no double bond in the latter. These monomers and their corresponding polymers were characterized for their liquid crystalline (LC) properties by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and X-ray diffraction.It was found that only the compounds bearing the planar cholesterol moieties possess LC phases. It is concluded that the 5a-configuration between the first and second cycles on the steroid skeleton of bile acids does not favor proper alignment of the rigid part of the bile acid moieties. It is interesting to see the effect of a small variation in structure on the properties of the otherwise structurally-similar compounds and the materials made from them. 相似文献
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Animal biles and gallstones are popularly used in traditional Chinese medicines, and bile acids are their major bioactive constituents. Some of these medicines, like cow-bezoar, are very expensive, and may be adulterated or even replaced by less expensive but similar species. Due to poor ultraviolet absorbance and structural similarity of bile acids, effective technology for species differentiation and quality control of bile-based Chinese medicines is still lacking. In this study, a rapid and reliable method was established for the simultaneous qualitative and quantitative analysis of 18 bile acids, including 6 free steroids (cholic acid, chenodeoxycholic acid, deoxycholic acid, lithocholic acid, hyodeoxycholic acid, and ursodeoxycholic acid) and their corresponding glycine conjugates and taurine conjugates, by using liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS). This method was used to analyze six bile-based Chinese medicines: bear bile, cattle bile, pig bile, snake bile, cow-bezoar, and artificial cow-bezoar. Samples were separated on an Atlantis dC18 column and were eluted with methanol–acetonitrile–water containing ammonium acetate. The mass spectrometer was monitored in the negative electrospray ionization mode. Total ion currents of the samples were compared for species differentiation, and the contents of bile acids were determined by monitoring specific ion pairs in a selected reaction monitoring program. All 18 bile acids showed good linearity (r2 > 0.993) in a wide dynamic range of up to 2000-fold, using dehydrocholic acid as the internal standard. Different animal biles could be explicitly distinguished by their major characteristic bile acids: tauroursodeoxycholic acid and taurochenodeoxycholic acid for bear bile, glycocholic acid, cholic acid and taurocholic acid for cattle bile, glycohyodeoxycholic acid and glycochenodeoxycholic acid for pig bile, and taurocholic acid for snake bile. Furthermore, cattle bile, cow-bezoar, and artificial cow-bezoar could be differentiated by the existence of hyodeoxycholic acid and the ratio of cholic acid to deoxycholic acid. This study provided bile acid profiles of bile-based Chinese medicines for the first time, which could be used for their quality control. 相似文献
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《Biomedical chromatography : BMC》2017,31(5)
Some biological properties of bile acids and their oxo derivatives have not been sufficiently investigated, although the interest in bile acids as signaling molecules is rising. The aim of this work was to evaluate physico‐chemical parametar b (slope) that represents the lipophilicity of the examined molecules and to investigate interactions of bile acids with carbonic anhydrase I, II, androgen receptor and CYP450s. Thirteen candidates were investigated using normal‐phase thin‐layer chromatography in two solvent systems. Retention parameters were used in further quantitative structure–activity relationship analysis and docking studies to predict interactions and binding affinities of examined molecules with enzymes and receptors. Prediction of activity on androgen receptor showed that compounds 3α ‐hydroxy‐12‐oxo‐5β ‐cholanoic and 3α ‐hydroxy‐7‐oxo‐5β ‐cholanoic acid have stronger antiandrogen activity than natural bile acids. The inhibitory potential for carbonic anhydrase I and II was tested and it was concluded that molecules 3α ‐hydroxy‐12‐oxo‐5β ‐cholanoic, 3α ‐hydroxy‐7‐oxo‐5β ‐cholanoic, 3,7,12‐trioxo‐5β ‐cholanoic acid and hyodeoxycholic acid show the best results. Substrate behavior for CYP3A4 was confirmed for all investigated compounds. Oxo derivatives of bile acids show stronger interactions with enzymes and receptors as classical bile acids and lower membranolytic activity compared with them. These significant observations could be valuable in consideration of oxo derivatives as building blocks in medicinal chemistry. 相似文献
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Shu Xian MENG Ya Qing FENG Wen Jin LI Cai Xia YIN Jin Ping DENG 《中国化学快报》2006,17(7):981-984
Chitosan, which is easily derived from chitin by N-deacetylation. It is well known that hypercholesterolemia has been identified as a major risk factor in the development of atherosclerosis and its clinical sequelae like coronary heart disease and myocard… 相似文献
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S Ikegawa J Kinoshita K Takeshita H Sato M Tohma 《Chemical & pharmaceutical bulletin》1989,37(8):2147-2152
Anti glyco-3 beta,12 alpha-dihydroxy-5-cholen-24-oic acid antisera were prepared by immunizing rabbits with hapten-bovine serum albumin (BSA) conjugates coupled at the C-3, C-15 alpha, and C-24 positions on the bile acid molecule, and their properties were investigated by heterologous combination assay using 125I-labeled tracer. The antiserum raised against the C-3 BSA conjugate showed poor titer and specificity, while the antisera from the other two conjugates showed satisfactorily high affinity constants (Ka = 5.0 x 10(8) and 7.0 x 10(8) M-1) and reasonable specificity, exhibiting negligible cross-reactivities with other major human bile acids and cholesterol. Among the unsaturated bile acids tested, high reactivity was observed with tauro-3 beta,12 alpha-dihydroxy-5-cholen-24-oic acid, which suggested that bridge phenomena were significant in this assay system. 相似文献
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This article describes some of the exciting results obtained during the study of the gelation behavior of bile acid derivatives in the authors laboratory. The serendipitous discovery of charge-transfer interaction promoted gelation of organic solvents by (steroid)pyrene derivatives/TNF is presented. In this class of molecules, the effect of the location of the chiral center in chiral gelators on the overall chirality of the aggregates in the gel was studied. Also described are the aggregation behavior of bile acid based aqueous gelators which led us to postulate design principals to obtain bile acid based aqueous/organogelators. 相似文献