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1.
目的:分离并鉴定黄芩药材中2',5,6',7-四羟基二氢黄酮醇。方法:依托以LipidA为靶点的抗内毒素(LPs)药物筛选平台,应用大孔吸附树脂、膜和高效液相色谱法对黄芩水提液进行针对LipidA的逐级分离纯化,对所得目标化合物采用质谱、核磁共振和红外光谱等技术进行结构解析。结果:从黄芩水提液中分离出活性化合物5KL-1B,其与LipidA的特异性结合值为208.6arc seconds,结构鉴定确证5KL-1B为2',5,6',7-四羟基二氢黄酮醇。结论:本试验建立的定向分离模式目的性强、效率高,可用于天然药物中抗LPS活性物质的富集与分离纯化。  相似文献   

2.
滇黄芩中新黄酮成分的结构研究   总被引:3,自引:0,他引:3  
胡碧煌  刘永漋 《药学学报》1989,24(3):200-206
从唇形科植物滇黄芩Scutellaria amoena C.H.Wright的根中分得八种黄酮类成分(Ⅰ~Ⅷ)。经理化常数测定、光谱分析和化学反应证明,Ⅰ和Ⅱ为新化合物,其结构分别为(2S)-2′,5,6′-三羟基-7-甲氧基双氢黄酮-2′-O-β-D-葡萄吡喃糖甙(Ⅰ)和(2 R,3 R)-2′,3,5,7-四羟基双氢黄酮(Ⅱ);其余六种为已知化合物,分别鉴定为(2S)-5,7,8-三羟基双氢黄酮(Ⅲ)、(2S)-2′,5,6′,7-四羟基双氢黄酮(Ⅳ)、(2 R,3 R)-2′,3,5,6′,7-五羟基双氢黄酮(Ⅴ)、2′,5,6′,7-四羟基黄酮(Ⅵ)、去甲汉黄芩素(Ⅶ)和千层纸甲素(Ⅷ),此六种化合物均为首次从该植物中得到。  相似文献   

3.
中间锦鸡儿黄酮类成分的研究   总被引:18,自引:0,他引:18  
施蛟  陈博  孙智华  胡昌奇 《药学学报》2003,38(8):599-602
目的研究中间锦鸡儿的化学成分。方法用溶剂法、色谱法分离化学成分,用波谱法鉴定其结构。结果从中间锦鸡儿中分离得到10个黄酮类化合物,分别鉴定为5,7,4′-三羟基-3,3′-二甲氧基黄酮(1),3,5,7,8,4′-五羟基-3′-甲氧基黄酮(2),槲皮素(3),柠檬黄酮醇(4),槲皮素-3-甲醚(5),2(S)-7,3′,5′-三羟基二氢黄酮(6),5,7,3′,4′-四羟基-3,8-二甲氧基黄酮(7),紫铆查尔酮(8),甘草素(9)和5,7,4′-三羟基-3,8二甲氧基黄酮(10)。结论化合物6为新化合物,其余皆首次从中间锦鸡儿中分离得到。  相似文献   

4.
马尾松松针中木脂素类成分的分离与鉴定   总被引:4,自引:0,他引:4  
目的研究松科植物马尾松(Pinus massoniana Lamb.)松针的化学成分。方法利用色谱技术分离纯化,根据化合物的理化性质和光谱数据进行结构鉴定。结果从马尾松松针水煎液的正丁醇部位分离得到3个化合物,分别鉴定为:(7S,8R)-3′,4,9′-三羟基-4-甲氧基-9-O-莽草酰基-7,8-二氢苯并呋喃-1′-丙基新木脂素(massonianoid A,I),(7S,8R)-4,9,9′-三羟基-3,3′-二甲氧基-7,8-二氢苯并呋喃-1′-丙基新木脂素(II),4,4′,8-三羟基-4,4′-二甲氧基-9-木脂内酯(III)。结论化合物I为新化合物,II和III为首次从本植物中分离得到。  相似文献   

5.
白花败酱草化学成分的分离与结构鉴定   总被引:3,自引:0,他引:3  
目的研究白花败酱草的化学成分。方法利用溶剂萃取后进行硅胶柱和制备液相色谱分离纯化,根据理化性质和光谱数据鉴定结构。结果分离并鉴定了8个化合物:bolusanthol B (1),(2S)-5,7,2′,6′-四羟基-6,8-二异戊烯基-二氢黄酮(2),orotinin (3),(2S)-5,7,2′,6′-四羟基-6-lavandulyl-二氢黄酮(4),3′-异戊烯基-芹黄素(5),木犀草素(6),槲皮素(7)和洋芹素(8)。结论化合物2,4为新化合物,1,3,5为首次从败酱属植物中分离得到,6,7,8为首次从白花败酱草中分离得到。  相似文献   

6.
滇黄芩化学成分的分离与鉴定   总被引:21,自引:1,他引:21  
目的研究滇黄芩 (ScutellariaamoenaC .H .Wright)化学成分。 方法利用各种色谱技术进行分离纯化 ,根据理化性质和光谱数据进行结构鉴定。结果分离得到 8个化合物 ,分别鉴定为 :5 ,7 二羟基 6 甲氧基二氢黄酮 (dihydrooroxylinA ,Ⅰ )、5 ,7,4′ 三羟基 8 甲氧基黄酮 ( 5 ,7,4′ trihydroxy 8 methoxyflavone ,Ⅱ )、千层纸素A(oroxylinA ,Ⅲ )、汉黄芩素 (wogonin ,Ⅳ )、白杨素 (chrysin ,Ⅴ )、黄芩素 (baicalein ,Ⅵ )、去甲汉黄芩素 (norwogonine ,Ⅶ )、( 2S) 5 ,7,2′ ,6′ 四羟基二氢黄酮 [( 2S) 5 ,7,2′ ,6′ tetrahydroxyflavanone ,Ⅷ ]。 结论化合物Ⅰ、Ⅱ为该植物中首次分得  相似文献   

7.
马尾松松针中木脂素类化学成分的研究   总被引:8,自引:0,他引:8  
目的研究松科(Pinaceae)植物马尾松(P.massoniana Lamb.)松针(pine needles)水煎液中的化学成分。方法利用Diaion HP-20,Toyopearl HW-40和硅胶等柱色谱技术进行分离纯化,根据化合物的理化性质和光谱数据进行结构鉴定。结果从马尾松针水煎液镇痛作用较强的正丁醇萃取部位分离得到3个木脂素类化合物,其化学结构分别确定为化合物7(massonianoside D): (7S,8r)-4,9′-二羟基-3,3′-二甲氧基-7,8-二氢苯骈呋喃-1′-丙醇基新木脂素-9-O-α-L-鼠李糖苷;化合物8(异落叶松脂素):4,4′,9,9′-四羟基-3,3′-二甲氧基-7-苯基四氢萘木脂素;化合物9(异落叶松脂素-9-O-木糖苷):4,4′,9′-三羟基-3,3′-二甲氧基-7-苯基四氢萘木脂素-9-O-β-D-木糖苷。结论化合物7为新化合物,化合物8,9为首次从本植物中分离得到。  相似文献   

8.
细茎石斛中抗氧化的有效成分研究   总被引:1,自引:0,他引:1  
目的 以细叶石斛Dendrobium moniliforme( Linn.) Sw.全草为研究对象,以DPPH法为抑制筛选体系,采用活性追踪的分离方法对猫眼草有效成分进行分离纯化,并对分离得到的化合物进行活性测定.方法 采用多种柱色谱法进行分离纯化,并根据理化常数和光谱分析进行结构鉴定.利用微板紫外比色法,体外测定各化合物对脂多糖(LPS)和干扰素γ-(IFN-γ)诱导的RAW264.7大鼠巨噬细胞NO的生成量.结果 分离得到了6个化合物,分别为4,4′-二羟基-3,3′,5-三甲氧基-,′-二羰基二苯乙烯(1),4,4′-二羟基-3,3′,5,α′-四甲氧基二苯乙烯(2),4,4′,α′-三羟基-3,3',5-三甲氧基二苯乙烯(3),反式-3,5-二羟基-5-甲氧基二苯乙烯(4),3,7-二羟基-2,4-二甲氧基菲(5),毛兰菲(6).结论 化合物1首次从该植物中分离得到,并且化合物1、2和3具,有较强的抑制大鼠巨噬细胞NO生成的作用,化合物3、5和6有强于白藜芦醇和芦丁的DPPH自由基捕捉削去作用.  相似文献   

9.
半枝莲的化学成分   总被引:13,自引:1,他引:13  
目的对黄芩属植物半枝莲(Scutellaria barbataD.Don)的抗肿瘤活性部位(氯仿萃取物和正丁醇萃取物)的化学成分进行分离、鉴定。方法用体积分数为70%的乙醇加热回流提取干燥药材,经石油醚、氯仿、正丁醇分步萃取,利用反复硅胶柱色谱、聚酰胺柱色谱、Sephadex LH 20凝胶柱色谱进行分离、纯化,根据理化性质和核磁共振氢谱、碳谱数据对所得化合物进行结构鉴定。结果得到8个化合物,分别鉴定为对羟基苯甲醛(1)、3,4二羟基苯甲酸(2)、对羟基苯乙酮(3)、5,7,4′三羟基8甲氧基黄酮(4)、5,7,4′三羟基6甲氧基黄酮(5)、5,7,4′三羟基黄酮(6)、5,4′二羟基6,7,3′,5′四甲氧基黄酮(7)、5羟基4′甲氧基黄酮7OαL鼠李糖基(1→6)βD吡喃葡萄糖苷(8)。结论化合物7、8为半枝莲中首次分离得到。  相似文献   

10.
剑叶血竭素国产血竭中一个新的二聚查耳酮   总被引:11,自引:0,他引:11  
目的 研究国产商品血竭的活性成分。方法 用甲醇提取,SephadexL-20,MCIgel和硅胶柱色谱进行分离纯化,用现代波谱学方法进行结构鉴定。结果 从国产雨林牌血竭的甲醇浸提物中得到9个查耳酮化合物,分别鉴定为:1-[5-(2,4,4′-三羟基二氢查耳酮基)]-1-对羟基苯基-3-(2-甲氧基-4-羟基苯基)-丙烷(1),2′-methoxysocotrin-5′-ol(2),socotrin-4′-ol(3),2-甲氧基-4,4′-二羟基二氢查耳酮(4),2,4,4′-三羟基二氢查耳酮(5),2,4,4′-三羟基-6-甲氧基二氢查耳酮(6),2′,4′,4-三羟基查耳酮(7),2-甲氧基-4,4′-二羟基查耳酮(8),2′-甲氧基-4′,4-二羟基查耳酮(9)。结论 1为一新的查耳酮二聚体,命名为剑叶血竭素(cochinchinenin),2-9为首次从该血竭中分离得到。  相似文献   

11.
结合药效的刺五加纯化工艺优选   总被引:2,自引:0,他引:2  
目的优选刺五加水提物的纯化工艺。方法将刺五加水提物分别采用D-101大孔树脂、聚酰胺和正丁醇萃取工艺纯化,测定紫丁香苷和总黄酮含量,并比较3种纯化样品对模型大鼠缺血再灌注损伤和模型小鼠断头张口的抗脑缺血作用。结果3种纯化样品均具有抗脑缺血作用,其中D-101大孔树脂纯化样品的作用强于其它2种样品;紫丁香苷含量与刺五加抗脑缺血作用成正相关。结论D-101大孔树脂吸附法是刺五加提取物较佳的纯化工艺。  相似文献   

12.
Polychlorinated biphenyls (PCBs) have been reported to be associated with increased risk to hypertension, atherosclerosis, cardiovascular disease, etc. 2,3′,4,4′,5-Pentachlorobiphenyl, known as PCB-118, is a member of coplanar PCBs which renders their structure similar to polychlorinated dibenzo-p-dioxins (PCDDs) and has dioxin-like activity. In our current study, we investigated the effect of PCB-118 exposure on nitric oxide (NO) production and the underlying mechanisms in vitro. Exposure of PCB-118 impaired insulin-induced NO production and endothelial nitric oxide synthase (eNOS) activity in human umbilical vein endothelial cells (HUVECs) with no significant effect on cell viability. Furthermore, PCB-118 treatment induced oxidative stress. In addition, scavenging of reactive oxygen species (ROS) by 10?μM N-acetyl-l-cysteine (NAC) partly rescued impaired insulin-induced eNOS activities and NO productions induced by PCB-118 in HUVECs. Taken together, these results indicate that PCB-118 mediates lower eNOS activity and impairs insulin-induced NO production partly through excessive ROS production in endothelial cells.  相似文献   

13.
Lipopolysaccharide (LPS) is a known trigger in the pathogenesis of sepsis, lipid A being the toxic component. One of several adjuvant therapeutic approaches for severe sepsis is currently focusing on the neutralization of LPS. In order to obtain the components from traditional Chinese herbs that can neutralize the endotoxin, aqueous extractions of twelve herbs were tested using affinity biosensor technology. From twelve herbs, Scutellaria baicalensis Georgi (Huang Qin) found to possess high lipid A-binding abilities, and was selected in subsequent experiments. After subjected to macroporous adsorptive resins and HPLC, we obtained 2',5,6',7-tetrahydroxyflavanonol (THF) from S. baicalensis Georgi under the direction of neutralization of LPS and reducing proinflammatory cytokines. In vitro, THF directly bound to LPS and neutralized its activity. THF not only down-regulated TNF-alpha mRNA expression but also decreased TNF-alpha and IL-6 release from RAW264.7 cells induced by LPS in a dose-dependent manner. THF-mediated inhibition on proinflammatory cytokine release is probably associated with downregulation of LPS-induced TLR4 mRNA augmentation. In vivo, THF could significantly protect mice against a lethal challenge with heat-killed E. coli 35218 (E. coli 35218) in a dose-dependent manner, and decreased the plasma LPS level in endotoxemia mice. These findings provide compelling evidence that THF may be an important potential drug for sepsis treatment. Considering the inhibitory effects of THF on LPS-induced cytokine release are unlikely due to its nonspecific cellular toxicity, THF should be considered as a safe putative candidate for development as a drug for sepsis treatment.  相似文献   

14.
Many studies suggest that one enzyme is involved in the phenolic ring deiodination of iodothyronines in rat liver and kidney and another one in the tyrosyl ring deiodination. This study describes some characteristics of the phenolic ring (5′-) deiodination of rT3 and 3′,5′-T2 by rat liver microsomes. At pH 7.2 the Km values of the 5′-deiodination of rT3 and 3′,5′-T2 were 0.103 and 0.77 μM, respectively. 3′,5′-T2 and rT3 inhibited the respective 5′-deiodination reactions competitively, the Ki values being 1.05 and 0.134 μM, respectively. Several radiographic contrast agents markedly inhibit the 5′-monodeiodination of rT3 and 3′,5′T-2, the type of inhibition being competitive. Of these compounds iopanoic acid, ipodic acid and iophenoxic acid are the most potent inhibitors with Ki values of approximately 2 μM for both reactions. The non-iodine containing compound 8-anilino-1-naphthalene sulphonic acid (ANS) appeared to be a very strong competitive inhibitor of both 5′-deiodinations (Ki 4.3–4.7 μM), whereas salicylic acid, which as ANS inhibits the binding of iodothyronines to T4-binding globulin, inhibited these reactions to a much lesser extent (Ki 300–500 μM). On the other hand, diiodosalicylic acid was a very strong inhibitor. The β-adrenergic blocker d,l-propranolol was a weak noncompetitive inhibitor of both 5′-deiodinations (Ki 0.4–0.7 mM). These reactions were also inhibited by various 2,6-diiodophenol derivatives, triiodophenol being the strongest and diiodotyrosine the weakest inhibitor tested. Comparing the Ki values of various inhibitors for the 5′-deiodination of rT3 and 3′,5′-T2, a positive correlation between these values was found (r = 0.97). It was concluded that rT3 (to 3,3′-T2) and 3′,5′-T2 (to 3′-T1) monodeiodinating activities are very similar to each other and that there may just be one monodeiodinase catalyzing the 5′-deiodination of iodothyronines in rat liver.  相似文献   

15.
The effects of an antifungal compound 2,4,3′,5′-tetrahydroxystilbene (THS)2 on oxidative phosphorylation by rat liver mitochondria were studied. THS at low concentrations was found to inhibit state 3 respiration (I50 = 44 nmoles/mg protein) but had no effect on uncoupled respiration induced by 2,4-dinitrophenol. The inhibitory effect of THS on state 3 respiration was observed with either glutamate or succinate as respiratory substrates. However when rat liver mitochondria were respiring with glutamate as substrate and in the presence of calcium chloride and inorganic phosphate, THS produced a strong inhibition of 2,4-dinitrophenol-stimulated respiration. This inhibition was over-come by adding succinate. The tetramethoxy derivative of THS had no effect on the mitochondrial reactions mentioned above suggesting that the phenolic groups are essential for the action of THS. The sites at which THS inhibits mitochondrial oxidative phosphorylation are proposed.  相似文献   

16.
In an attempt to improve the antiviral efficacy of 5′-amino-2′,5′-dideoxy-5-iodouridine (AIdU) the N-acetyl and N,3′-O-diacetyl derivatives were prepared. N-Acetylation of AIdU increased its ability to inhibit the phosphorylation of thymidine by the deoxypyrimidine kinase of herpes simplex virus type 1 (HSV1) while diacetylation had the converse effect. The affinity of the corresponding compounds containing uracil or thymine for virus deoxypyrimidine kinase was also determined. A range of N-acyl-, N-sulphonyl- and N,3′-O-diacyl- derivatives of AIdU were synthesised; enhanced inhibition of deoxypyrimidine kinase by a number of these compounds was observed. The previous observation that 5′-azido-2′,5′-dideoxy-5-iodouridine has antiherpetic activity in vivo led us to investigate its 3′-O-acetyl derivative as well as the corresponding compound containing uracil. None of the derivatives described showed antiviral activity in cell culture against HSV1; acylation failed to enhance the potency of AIdU against HSV1 in vivo.  相似文献   

17.
目的 改进抗肿瘤药物卡培他滨的合成工艺。方法 以5-氟胞嘧啶为原料,经硅醚化后,与 5´-脱氧-1´,2´,3´-三-乙酰基-D-核糖缩合,再经酰胺化、水解制得卡培他滨。结果与结论 目标化合物的结构经1H-NMR、IR、MS 谱确证,总收率为70.0%,改进后的工艺,简化了实验操作,解决了重金属超标问题,有利于工业化生产。  相似文献   

18.
目的研究甲状腺激素类似物3,3′,5-三碘甲状丙酸(Triprop,1)的合成工艺。方法以3,5-二碘-4-羟基苯丙酸甲酯为原料,采用醋酸铜参与的芳基硼酸与酚的偶联反应来构建二芳基醚骨架,完成了Triprop的合成。结果与结论该路线共计4步反应,总收率达40.3%,系首次将醋酸铜参与的芳基硼酸与酚的偶联反应用于Triprop的合成。  相似文献   

19.
In this study, we investigated the mechanisms of 3′,4′,7-trihydroxyflavone (THF) protection of neuronal cells from neuronal cell death induced by the oxidative stress-related neurotoxin hydrogen peroxide (H2O2). Pretreatment with THF significantly elevated cell viability, reduced H2O2-induced lactate dehydrogenase (LDH) release, reactive oxygen species (ROS) production, glutathione (GSH) content, superoxide dismutase (SOD) activity, catalase (CAT) activity, and mitochondria membrane potential (MMP) loss. Western blot data demonstrated that THF inhibited the H2O2-induced up- or down-regulation of cleaved caspase-3, cleaved caspase-9, cleaved poly-ADP-ribose polymerase (PARP), Bax, Bcl-2, and Bcl-xL, and attenuated the H2O2-induced release of cytochrome c from the mitochondria to the cytosol. In addition, pretreatment with THF attenuated H2O2-induced rapid and significant phosphorylation of c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), and phosphatidylinositol 3-kinases (PI3K)/Akt. THF also inhibited nuclear factor-κB (NF-κB) translocation to the nucleus induced by H2O2, down-stream of H2O2-induced phosphorylation of MAPKs and PI3K/Akt. These data provide the first evidence that THF protects neuronal cells against H2O2-induced oxidative stress, possibly through ROS reduction, mitochondria protection, and NF-κB modulation via MAPKs and PI3K/Akt pathways. The neuroprotective effects of THF make it a promising candidate as a therapeutic agent for neurodegenerative diseases.  相似文献   

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