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1.
目的:设计合成甘草次酸–苦参碱复合物,并对其体外抗肿瘤活性进行研究。方法以槐果碱、18α-甘草次酸和18β-甘草次酸为原料,经过加成、氧化、酯化缩合等反应合成目标化合物甘草次酸–苦参碱复合物,并采用MTT法对其进行体外抗肿瘤活性研究。结果设计并合成了目标产物甘草次酸–苦参碱复合物,利用MS和1H-NMR确证了结构;体外活性实验中,甘草次酸–苦参碱复合物的抗肿瘤活性明显高于甘草次酸及苦参碱,并优于对照药美法仑。结论甘草次酸–苦参碱复合物具有良好的抗肿瘤活性,尤其对肝癌细胞生长产生较好的抑制作用,值得进一步进行研究。  相似文献   

2.
海洋放线菌11014中抗肿瘤活性成分的研究Ⅰ.环二肽   总被引:17,自引:2,他引:17  
为研究具有抗肿瘤活性的海洋放线菌11014发酵物中的活性成分,采用活性追踪的方法.经溶剂萃取、硅胶柱层析及制备HPLC等分离得到13个环二肽,通过理化性质及波谱学分析,分别确定为环(亮氨酸-丙氨酸).环(亮氨酸-甘氨酸),环(异亮氨酸-丙氮酸),环(缬氮酸-丙氮酸).环(丙氨酸-苯丙氮酸),环(苯丙氮酸-甘氮酸).环(酪氮酸-甘氮酸),环(脯氮酸-酪氮酸),环(脯氨酸-苯丙氨酸),环(4-羟基-脯氮酸-苯丙氮酸).环(4-羟基-脯氮酸-亮氨酸).环(脯氮酸-缬氨酸),环(脯氮酸-亮氨酸)。首次以磺酰罗丹明法对这些化合物的抗肿瘤活性进行了测试,化合物环(4-羟基-脯氨酸-苯丙氨酸)具有较明显的抗肿瘤活性(5μg/ml浓度抑制率为48.3%)。  相似文献   

3.
本文综述了1967-1992年有关天然松香烷酸及其衍生物的生物活性,抗微生物,抗溃疡及心血管活性是该二匝一类化合物最有代表性的活性,而对决定松香烷酸不同胜任的其他方面的活性,如过敏,抗过敏,成膜,表面活性,拒食等活性也作了报道。  相似文献   

4.
夫西地酸对革兰阳性球菌的体外敏感性分析   总被引:1,自引:0,他引:1  
摘要:目的检测夫西地酸对临床常见革兰阳性球菌的体外抗菌活性。方法用纸片扩散法检测夫西地酸对葡萄球菌和肠球菌的抑菌活性,并与其他常用抗生素比较。同时用琼脂稀释法检测部分菌株的夫西地酸最低抑菌浓度(MIC)。结果在121株菌株中MRSA34株,MRCNS41株,粪肠球菌15株,屎肠球菌10株。对夫西地酸的耐药率分别为2.9%、4.8%、100.0%和100.0%,略高于万古霉素,明显低于其他常用的抗生素(如红霉索、头孢唑林,环丙沙星等)。夫西地酸对MRSA、MRCNS的抗菌活性明显高于肠球菌。结论夫西地酸对MRS有较高的体外抗菌活性。夫西地酸对肠球菌并无杀菌作用。  相似文献   

5.
报道3β,5α,6β三羟基胆烷24酸及其衍生物的合成及对小鼠L1210白血病细胞的体外抗癌活性.实验表明3β,5α,6β三羟基胆烷24酸,3β,5α,6β三羟基胆烷24酸甲酯及3β,6β二乙酰氧基5α羟基胆烷24酸甲酯有较好的抗癌活性  相似文献   

6.
白桦酸及其衍生物的研究进展   总被引:13,自引:0,他引:13  
李丹  周金培  吴晓明 《药学进展》2004,28(3):120-125
对白桦酸衍生物的构效关系及其中的YK-FH312、RPR103611和IC9564等的作用机制及活性进行述评。天然产物白桦酸是有抗HIV和抗肿瘤活性,且具有新型结构和新型作用机制的化合物,其天然来源广泛,半合成方法成熟,是寻找抗HIV和抗肿瘤药物的优秀的先导物。通过对白桦酸的结构修饰,大量白桦酸衍生物已被合成。  相似文献   

7.
羟基胆烷酸类衍生物的抗癌活性研究   总被引:2,自引:2,他引:0  
报道3β,5α,6β-三羟基胆烷-24-酸及其生物的合成及对小鼠L1210白血病细胞的体外抗癌活性,实验表明,3β,5α,6β-三羟基胆烷-24-酸,3β,5α,6β-三羟基胆烷-24-酸甲酯及3β,6β-二乙酰氧基-5α-羟工胆烷-24-酸甲酯有较好的抗癌活性。  相似文献   

8.
松罗酸的提取和抗癌活性研究   总被引:2,自引:0,他引:2  
由长松萝中分离得以萝酸粗品、精品并制成钠盐。3种试品的Brineshrimp生物活性测定结果LC50均小于50,松萝酸钠活性最高。松萝酸粗品(50-120mg/kg)对小鼠S80肉瘤的抑制率大于65%,表明松萝酸具有较强的抗癌活性。  相似文献   

9.
以脂磷壁酸为靶点的新抗筛选模型的建立和应用   总被引:3,自引:0,他引:3  
目的:根据达托霉素的作用机制,寻找与糖肽类抗生素无交叉耐药性的新抗生素,方法:本实验建立了以脂磷壁酸为靶点的新抗筛选模型,并通过脂磷壁酸合成抑制模型对所筛得的阳性菌株进行复筛验证。结果:从1200株放线菌中筛选到2株阳性菌株,初步证明其抗菌活性显示出Ca^2 依赖性,并在脂磷壁酸合成抑制模型上显示一定的抑制活性。结论:阳性菌株1510和1615活性成分对MRSA等细菌具有良好的抗菌活性,值得深入研究。  相似文献   

10.
目的 建立超滤质谱快速筛选赤芍活性成分的方法,从中得到可能的潜在抗凝血活性成分。方法 对赤芍不同极性部位成分进行鉴定,以凝血酶(thrombin, THR)为靶标,亲和超滤法逆靶向筛选赤芍中的凝血酶抑制剂,并对得到的活性成分进行分析、鉴定;采用生色底物法及体外抗凝法对其进行活性验证,通过分子对接对其结合能力进行初步分析。结果 经对赤芍不同极性部位成分进行定性分析,检测出17个成分,并通过亲和超滤质谱法筛选得到一个可能的抗凝血活性成分——鞣花酸。鞣花酸浓度为1 g·L-1时对凝血酶百分抑制率可达98.34%;体外凝血实验发现鞣花酸凝血酶时间(thrombin time, TT)与空白组相比有显著性差别(P<0.01),表明其为潜在的凝血酶直接抑制剂;分子对接结果显示鞣花酸与凝血酶活性结合位点多、结合能低,具有良好的结合效果。结论 建立了一种快速筛选赤芍中抗凝血活性成分的方法,筛选结果表明鞣花酸可能为潜在的凝血酶抑制剂,为中药的靶向治疗、机制探索和质量控制提供了有价值的参考。  相似文献   

11.
The actions of kainic acid and its derivatives including the new tricarboxylic kainic acid were tested on the Hermit crab neuromuscular junction. Kainic acid had a direct excitatory effect producing a depolarization. Although not so potent, alpha-ketokainic acid and tricarboxylic kainic acid mimicked this effect whilst dihydrokainic acid did not. The slopes of the dose-response curves for these kainic acid analogues differed from that of L-glutamate. A Hill coefficient approximating one was obtained for kainic acid compared to a value of three for L-glutamate. Threshold concentrations of l-glutamate and kainic acid but not alpha-ketokainic acid and tricarboxylic kainic acid potentiated the neurally evoked excitatory junction potentials and the ionophoretic L-glutamate potential. The results indicate a possible interaction of the kainic acid derivatives with a heterogeneous receptor population and provide a comparison with other invertebrate and vertebrate systems.  相似文献   

12.
海金沙提取物中香豆酸和咖啡酸的测定及稳定性研究   总被引:2,自引:0,他引:2  
目的建立了海金沙提取物中香豆酸和咖啡酸的测定方法,并研究了二者在不同条件下的稳定性。方法选用E-clipse XDB-C18色谱柱,以甲醇-1%乙酸水溶液作为流动相进行梯度洗脱;考察了光照、放置时间等因素对咖啡酸和香豆酸稳定性的影响。结果香豆酸和咖啡酸得到很好的分离。以水为溶剂,咖啡酸和香豆酸在冷藏避光条件下储存比较稳定。结论为香豆酸和咖啡酸的提取、分析及其相关制剂的生产提供参考。  相似文献   

13.
Dietary polyphenols are thought to be beneficial for human health as antioxidants. Coffee beans contain a common polyphenol, chlorogenic acid. Chlorogenic acid is the ester of caffeic acid and quinic acid. Although these polyphenols have received much attention, there is little evidence indicating a relationship between the effect and the rate of absorption. In this study, we focused on the beneficial effects of chlorogenic acid and caffeic acid, a major metabolite of chlorogenic acid. We carried out in vitro and in vivo experiments. In the in vitro study, caffeic acid had stronger antioxidant activity than that of chlorogenic acid. The uptake of chlorogenic acid by Caco-2 cells was much less than that of caffeic acid. The physiological importance of an orally administered compound depends on its availability for intestinal absorption and subsequent interaction with target tissues. We then used an intestinal ischemia-reperfusion model to evaluate antioxidant activities in vivo. We found that both chlorogenic acid and caffeic acid had effects on intestinal ischemia-reperfusion injury. Since caffeic acid has a stronger antioxidant activity than that of chlorogenic acid and chlorogenic acid is hydrolyzed into caffeic acid in the intestine, it is possible that caffeic acid plays a major role in the protective effect of chlorogenic acid against ischemia-reperfusion injury.  相似文献   

14.
The effect of chlorogenic acid on the sleep-wakefulness cycle in rats was investigated in comparison with those of caffeic acid (the metabolite of chlorogenic acid) and dihydrocaffeic acid (the metabolite of caffeic acid). A significant prolongation of sleep latency was observed with chlorogenic acid and caffeic acid at a dose of 500 and 200 mg/kg, respectively. On the other hand, no remarkable effects were observed with dihydrocaffeic acid even at a dose of 500 mg/kg. Caffeine caused a significant increase in sleep latency and waking time and decrease in non-rapid eye movement sleep time at a dose of 10 mg/kg. In contrast, chlorogenic acid and its metabolites had no significant effects on each sleep state. From these results, it may be concluded that chrologenic acid caused a mild arousal effect compared with that of caffeine, and the effect of chlorogenic acid may have occurred through its metabolite caffeic acid.  相似文献   

15.
Retinoic acid isomers have been used with some success as chemotherapeutic agents, most recently with 13-cis retinoic acid showing impressive clinical efficacy in the paediatric malignancy neuroblastoma. The aim of this commentary is to review the evidence that 13-cis retinoic acid is a pro-drug, and consider the implications of retinoid metabolism and isomerisation for the further development of retinoic acid for cancer therapy. The low binding affinity of 13-cis retinoic acid for retinoic acid receptors, low activity in gene expression assays and the accumulation of the all-trans isomer in cells treated with 13-cis retinoic acid, coupled with the more-favourable pharmacokinetic profile of 13-cis retinoic acid compared to other isomers, suggest that intracellular isomerisation to all-trans retinoic acid is the key process underlying the biological activity of 13-cis retinoic acid. Intracellular metabolism of all-trans retinoic acid by a positive auto-regulatory loop may result in clinical resistance to retinoic acid. Agents that block or reduce the metabolism of all-trans retinoic acid are therefore attractive targets for drug development. Devising strategies to deliver 13-cis retinoic acid to tumour cells and facilitate the intracellular isomerisation of 13-cis retinoic acid, while limiting metabolism of all-trans retinoic acid, may have a major impact on the efficacy of 13-cis retinoic acid in paediatric oncology.  相似文献   

16.
Pyruvic acid, α-ketobutyric acid, α-ketovaleric acid, α-ketooctanoic acid, α-ketononanoic acid, α-ketoisovaleric acid, α-ketoglutaric acid, α-ketoadipic acid, hydroxypyruvic acid, and 4-pentenoic acid did not induce significant insulin secretion from the perfused rat pancreas, β-phenyl-pyruvic acid and α-keto-β-methylvaleric acid induced only minimal insulin secretion from the perfused rat pancreas which was characterized by a monophasic secretory pattern. Both α-ketocaproic acid and α-ketoisocaproic acid were potent insulin secretagogues which induced a biphasic insulin secretory pattern comparable to the secretory pattern in response to glucose. The insulin secretory potency of this group of chemically related α-ketoacids is discussed.  相似文献   

17.
Ruminococcus sp. PO1-3, an intestinal bacterium isolated from human feces, metabolized glycyrrhizin (GL) to glycyrrhetic acid (GA) and GA to 3-oxo-glycyrrhetic acid (3-oxo-GA) and possessed GL beta-D-glucuronidase and 3beta-hydroxysteroid dehydrogenase (3beta-HSD) involved in the metabolism of GL. This bacterial growth was enhanced by GL at a concentration of 0.4 mm and was suppressed by GA at concentration of 1.0 mM. Chenodeoxycholic acid, deoxycholic acid and lithocholic acid among the bile acids added to this bacterium suppressed the growth and GL beta-D-glucuronidase activity and 3beta-HSD activity incident to it at a concentration of 1.0 mM, while cholic acid, hyodeoxycholic acid and glycine and taurin conjugates of cholic acid, chenodeoxycholic acid, deoxycholic acid and lithocholic acid had almost no effect on this bacterium at a concentration of 0.2 to 1.0 mm. However, these enzyme activities of this sonicated bacteria were inhibited by all of these bile acids. Although each bile acid and GL added to bacteria at the same time suppressed the growth and the amount of metabolite GA by all bile acids used except cholic acid, taurocholic acid and taurodeoxycholic acid with GL, a combination of each bile acid and GA eased the growth inhibition caused by GA at a concentration of 0.2 mM and enhanced the amount of metabolite 3-oxo-GA by the glycine conjugate of bile acids with GA. GL or GA added after 6 h culture with each of these bile acids and bacteria was metabolized to a relatively large amount of GA by chenodeoxycholic acid and lithocholic acid and their glycine and taurine conjugates, glycocholic acid and taurodeoxycholic acid, or had almost no effect on the amount of metabolite 3-oxo-GA, respectively. These results showed that although GL added after the exposure to bile acid and GA and bile acid added at the same time as bacteria had different bile acid action, these conditions enhanced the amount of metabolite GA from GL and metabolite 3-oxo-GA from GA.  相似文献   

18.
Valproic acid is an anticonvulsant widely used for the treatment of epilepsy. However, valproic acid is known to show fetal toxicity, including teratogenicity. In the present study, to elucidate the mechanisms of valproic acid transport across the blood-placental barrier, we carried out transcellular transport and uptake experiments with human placental choriocarcinoma epithelial cells (BeWo cells) in culture. The permeability coefficient of [3H]valproic acid in BeWo cells for the apical-to-basolateral flux was greater than that for the opposite flux, suggesting a higher unidirectional transport in the fetal direction. The uptake of [3H]valproic acid from the apical side was temperature-dependent and enhanced under acidic pH. In the presence of 50 microM carbonyl cyanide p-trifluoromethoxylhydrazone, the uptake of [3H]valproic acid was significantly reduced. A metabolic inhibitor, 10 mM sodium azide, also significantly reduced the uptake of [3H]valproic acid. Therefore, valproic acid is actively transported in a pH-dependent manner on the brush-border membrane of BeWo cells. Kinetic analysis of valproic acid uptake revealed the involvement of a non-saturable component and a saturable component. The Michaelis constant for the saturable transport (K(t)) was smaller under acidic pH, suggesting a proton-linked active transport mechanism for valproic acid in BeWo cells. In the inhibitory experiments, some short-chain fatty acids, such as acetic acid, lactic acid, propanoic acid and butyric acid, and medium-chain fatty acids, such as hexanoic acid and octanoic acid, inhibited the uptake of [3H]valproic acid. The uptake of [3H]valproic acid was also significantly decreased in the presence of 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid, salicylic acid and furosemide, which are well-known inhibitors of the anion exchange system. Moreover, p-aminohippuric acid significantly reduced the uptake of [3H]valproic acid. These results suggest that an active transport mechanism for valproic acid exists on the brush-border membrane of placental trophoblast cells and operates in a proton-linked manner.  相似文献   

19.
目的以牛血清白蛋白为例建立用脂肪酸修饰活性蛋白质的工艺。方法通过脂肪酸的酰氯在酸催化下50℃与N-羟基琥珀酰亚胺反应制备活化酯,再与蛋白质发生偶联形成产物,利用红外谱图对反应产物进行鉴定。结果月桂酸、棕榈酸等脂肪酸与氯化亚砜回馏3 h很容易得到相应的脂肪酰氯,酰氯在酸催化下50℃与N-羟基琥珀酰亚胺反应3 h可以将N-羟基琥珀酰亚胺转变成活性酯,产率为90%,脂肪酸的活性酯在pH=8的缓冲液可以偶联到活性蛋白质上,活化酯转化率为87.9%。结论建立了脂肪酸修饰活性蛋白质的工艺。  相似文献   

20.
磷酸水解法制备复合氨基酸及铁锌氨基酸口服液的研究   总被引:2,自引:0,他引:2  
建立一种制备氨基酸口服液的新方法。方法:采用猪血作为复合氨基酸的主要来源,对猪血蛋白的磷酸水解工艺进行了研究。结果:猪血水解液中含有17种氨基酸,其中必需氨基酸7种;与盐酸水解法和硫酸水解法比较,磷酸水解法制备的氨基酸口服液稳定性和口感均有较大改善。结论:磷酸水解法是制备复合氨基酸较好的方法。通过添加铁、锌、牛磺酸和中草药制备的氨基酸口服液更具有营养价值。  相似文献   

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