149 resultados para Quantitative structure-property relationship
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A systematic and quantitative research on the structure-property correlation has been carried out in KH2PO4 (KDP), NH4H2PO4 (ADP) and HIO3, based on the dielectric theory of complex crystals and the Levine bond charge model. We, for the first time, successfully solve the problems in the calculation of the nonlinearities of the complex inorganic nonlinear optical (NLO) crystals, which have O-H bonds in their crystal structures. We do this by introducing the bond-valence equation we have set up, calculating the nonlinear optical tensor coefficients d(ijk) of these three compounds, quantitatively determining the contributions of each type of bond to the total second-order NLO tensor coefficient (d(ijk)) of the crystal, and presenting the bond parameters and the linear properties of each kind of bond. For the first time, the NLO coefficient d(36) for ADP was calculated. All calculated results are in good agreement with experimental data. We found that O-H bonds also play an important role in these crystals, except for in the important anionic groups (PO4 groups and IO3 groups). All the results thus calculated show that our method is useful in evaluating the NLO coefficients of the inorganic NLO crystals containing O-H bonds in their structures, and should be a useful tool toward the future research into new nonlinear optical materials of this kind.
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The conformation analysis and study on structure-taste relation-ships of 4 taste compounds have been performed, the results reveal that the sweetnees will decrease with the increase of the specific dihedral angle O-1-C-2-C-3-C-4, and the mechanism was intepreted.
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Snake venom Kunitz/BPTI members are good tools for understanding of structure-functional relationship between serine proteases and their inhibitors. A novel dual Kunitz/BPTI serine proteinase inhibitor named OH-TCI (trypsin- and chymotrypsin-dual inhibito
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mRNA 所包含的核苷酸序列通过三联体密码子决定了蛋白质的氨基酸序列。但是, 由于对氨基酸同 义密码使用频率上的差异, 密码子与反密码子相互作用效率上的不同, 以及密码子上下文关系和mRNA 不同区 域二级结构上的差异, 造成了核糖体对mRNA 不同区域翻译速度上的差异, 加之共翻译折叠的作用, 使得mR2 NA 的序列和结构影响着蛋白质空间结构的形成。
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基于土地利用数量结构与功能特征对应变换关系,选取相关定量指标,以安徽省含山县为例,探讨县域土地利用数量结构与功能特征关联分析方法。结果表明:定量分析具有可行性,操作性强,较为简便。一定程度上,多样性、均匀度景观生态综合功能指标与组合类型数呈同向关联,而优势度与其呈反向关联,经济密度、人口密度社会经济综合功能指标与土地利用程度、建设用地区位指数呈同向关联。
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目的研究TCS抗HIV-1的构效关系并对机制进行探讨。方法蛋白工程技术构建14个TCS突变 体,测定各种TCS突变体的细胞毒性和抗HIV恬性。结果活性中心突变体TCSM(120—123)与TcSEl60A/E189A在失 去绝大部分RI活性的同时,也几乎完全失去抗HIV活性。而另一个活性中心突变体TCSRl22G,RI活性下降160 倍,却仍保留一定的抗HIV活性。TCSC末端删除突变体(TCS(2,TCSo和TCScl。)抗HIV活性的下降(1.4—4.8 倍)与其RI活性呈平行下降(1.2—3.3倍);分别在C末端加上末端19个氨基酸延伸肽或KDEL信号肽的突变体 TCscl9。与TQkDEL,虽然保留全部的RI活性,但却几乎完全失去抗HIV活性;TCS抗原决定簇位点突变后对TCS 抗HIV.1括性没有显著影响,但当在抗原决定簇突变体所引入的Cys残基上加上PEG20K后,这些突变体则显著降 低了抗HIV-1的活性。TCS不能抑制HIV一1进入宿主细胞;对感染细胞和未感染细胞的融合没有抑制作用;TCS 也不能抑制HIV一1 rRT活性;TCS对病毒颗粒的直接杀伤作用不大。结论TCS抗HIV-1活性与其Rl活性显著 相关,但似乎又不是唯一的决定因素;TCS C末端氨基酸的突变影响其抗HIV.1活性;在C末端增加KDEL信号肽 序列及19aa尾肽并不能增加其抗HIV活性;抗原决定簇突变体以及PEG20K偶联TCS抗原决定簇突变体体外抗 HIV-1活性下降;抗HIV.1机制可能与对感染细胞的间接作用有关。
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天花粉蛋白(Trichosanthin,TCS)是从葫芦科植物括楼(TrichosanthesKiriloii)球根中提取的一种由247个氨基酸组成的I型核糖体失活蛋白(RibosomeInactivatingProtein,RIP)。TCS具有广谱的生物学和药学活性,包括抗肿瘤、免疫抑制、中期引产以及抗病毒活性,TCS还具有抗白血病和淋巴瘤的作用。TCS能够抑制HI卜1在急性感染的T淋巴细胞和慢性感染的巨噬细胞中的复制。TCS抗HIV的机制还不清楚,一般认为与R1(RibosolneInactivating)活性有关。TCS的毒副作用限制了它在抗HIV/AIDS临床上的进一步应用。人们期望通过改造或修饰,在保留TCS抗HIV活性的同时,降低其神经毒副作用及所引起的变态反应。因此,研究TCS的抗HIV-1作用机制及构效关系,有利于拓宽TCS的临床应用适应症,也对RIP类化合物基础研究和应用研究具有重要的指导作用。本论文在实验室己有研究工作的基础上,对TCS抗HIV-1作用、机制及构效关系进一步研究。首先,采用MTT比色法检侧TcS对人T淋巴细胞系C8166、HIV-1慢性感染细胞系H9/HIV-1IIIB细胞毒性作用以及采用台盼蓝染色法检测了TCs对刺激转化的人外周血单个核细胞(PeriphejralBloodMononuclearCen,PBMC)的细胞毒性作用;以合胞体形成抑制实验检测了TCS对实验株HIV-1ms诱导C8166细胞致细胞病变的抑制作用;以捕捉HIV-1p24抗原ELISA方法检测TCS对实验.株HIV-1IIIB在急性感染C8166,细胞和慢性感染Hg细胞中复制的抑制作用、临床分离株HIV-1KMO18在PBMC中复制的抑制作用、耐药株HIV-174v在C8166细胞中复制的抑制作用。其次,利用荧光实时定量RT-PCR检测了TCS对HIV-IIIB吸附和融合宿主细胞的抑制作用;采用高效液相色谱(HighPerformanceLiquidChromatograPhy,HPLC)检测了TCS脱HIV-IRNA腺嘿呤作用;另外还检测了TCS对病毒颗粒的直接杀伤作用、TCS对HIV感染和未感染细胞融合的抑制以及对HIV重组逆转录酶活性的抑制作用。最后,利用以蛋白工程技术构建的14个TCD突变体研究其抗HIV的构效关系,其中活性中心突变体:结果表明,TCS不仅能够有效抑制实验株HIV-1mB在C8166细胞中的复制和HIV-1ms诱导宿主细胞的病变作用,还能抑制临床分离株HIV-1KM018在PMBC中的复制和耐药株HIV-174v在C8166细胞中的复制,但TCS对HIV-1在慢性感染H9细胞中的复制无直接抑制作用。TCS不能抑制HIV-1进入宿主细胞;对感染细胞和未感染细胞的融合没有抑制作用;TCS也不能抑制HIV-1重组逆转录酶活性;TCS对病毒颗粒的直接杀伤作用不大;但TCS能够使裸露的HIV-1RNA脱腺漂呤,可能TCS的脱缥岭活性或其它酶活性直接损伤病毒或者病毒感染细胞的核酸,而胞质腺嗦岭含量的增高则可以导致线粒体膜电位的降低、细胞色素C的释放、活性氧的增加和抗凋亡因子表达的下降,结果使感染细胞更多的凋亡,这可能是TCS抗HIV的一个机制。结果也表明,活性中心突变体TCSM(120-123)与TCSE160A/E189A,在失去绝大部分R工活"性的同时,也几乎完全失去抗HIV活性。、而另一个活性中心突变体TCSR122G,RI活性下降1的倍,却仍保留一定的抗HIV活性。TcSC末端删除突变体(TCSC2,TCSC4和TCSC14)抗HIV活性的下降(1.4-4.8倍)与其R1活性呈平行下降(1.2-3.3倍)。这些结果表明TCS抗HIV-1活性与其R1活性显著相关,但似乎又不是唯一的决定因素,因为我们发现二个分别在C末端加上末端19个氨基酸延伸肤或KDEL信号肤的突变体TCS饥触与TCSKDEL,虽然保留全部的RI活性,但却几乎完全失去抗HIV活性,表明有其它机制介入了TCS的抗HIV-1活性。TCS抗原决定簇位点突变后对TCS抗HIV-1活性没有显著影响,但当在抗原决定簇突变体所引入的Cys残基上加上PEG漱后,这些突变体则显著降低了抗HIV-1的活性。
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1、喜树碱类衍生物抗HIV构效关系与作用机制研究 喜树碱为传统的抗肿瘤药物。本研究对经过化学结构修饰的喜树碱类衍生物进行抗HIV活性及作用机制的研究,并初步探讨了其抗HIV构效关系。 我们对喜树碱类衍生物A系列化合物A1(喜树碱)、A2(10-羟基喜树碱)及A3(7-羟基喜树碱)进行了抗HIV活性检测。化合物A1和A3有较好的抗HIV-1和抗HIV-2活性,化合物A2没有显示抗HIV活性。表明化合物A1的C-10位上-OH基团修饰可能会降低抗HIV活性,化合物A1的C-7位上-CH2OH基团修饰和C-20位-CH3缺失可能会提高其抗HIV活性。对化合物A3和A1的抗HIV机制研究发现:二者对整合酶有一定的结合活性,对慢性感染H9/HIV-1ⅢB 和Jurkat/HIV-1ⅢB细胞中病毒复制没有抑制活性、不能阻断H9/HIV-1ⅢB与正常细胞间的融合,对重组的HIV-1蛋白酶和逆转录酶没有抑制活性。化合物A1和A3不具有选择性杀伤HIV-1ⅢB慢性感染的H9和Jurkat细胞系的作用。进一步进行化合物A3诱导 H9和H9/HIV-1ⅢB、Jurkat和Jurkat/HIV-1ⅢB的凋亡实验显示,化合物A3诱导感染HIV-1ⅢB和未感染病毒细胞的凋亡没有选择性。据此我们初步认为化合物A3和A1的抗HIV作用可能与抑制整合酶活性有关,该化合物可能还作用于其它靶点。 喜树碱类衍生物B系列中化合物B1为20(S)-O - [-O-( 1'-氧基-2',2',6',6'-四甲基哌啶-4'-丁二酸)]-20-喜树碱酯,化合物B2为20(S)-O - [-N-( 1'-氧基-2',2',6',6'-四甲基-1',2',5',6'-四氢吡啶酰胺)-4'-丙氨酸)]-20-喜树碱酯)。我们对化合物B1和B2进行了抗HIV活性检测。结果显示:化合物B2有较好的抗HIV-1和抗HIV-21、喜树碱类衍生物抗HIV构效关系与作用机制研究 喜树碱为传统的抗肿瘤药物。本研究对经过化学结构修饰的喜树碱类衍生物进行抗HIV活性及作用机制的研究,并初步探讨了其抗HIV构效关系。 我们对喜树碱类衍生物A系列化合物A1(喜树碱)、A2(10-羟基喜树碱)及A3(7-羟基喜树碱)进行了抗HIV活性检测。化合物A1和A3有较好的抗HIV-1和抗HIV-2活性,化合物A2没有显示抗HIV活性。表明化合物A1的C-10位上-OH基团修饰可能会降低抗HIV活性,化合物A1的C-7位上-CH2OH基团修饰和C-20位-CH3缺失可能会提高其抗HIV活性。对化合物A3和A1的抗HIV机制研究发现:二者对整合酶有一定的结合活性,对慢性感染H9/HIV-1ⅢB 和Jurkat/HIV-1ⅢB细胞中病毒复制没有抑制活性、不能阻断H9/HIV-1ⅢB与正常细胞间的融合,对重组的HIV-1蛋白酶和逆转录酶没有抑制活性。化合物A1和A3不具有选择性杀伤HIV-1ⅢB慢性感染的H9和Jurkat细胞系的作用。进一步进行化合物A3诱导 H9和H9/HIV-1ⅢB、Jurkat和Jurkat/HIV-1ⅢB的凋亡实验显示,化合物A3诱导感染HIV-1ⅢB和未感染病毒细胞的凋亡没有选择性。据此我们初步认为化合物A3和A1的抗HIV作用可能与抑制整合酶活性有关,该化合物可能还作用于其它靶点。 喜树碱类衍生物B系列中化合物B1为20(S)-O - [-O-( 1'-氧基-2',2',6',6'-四甲基哌啶-4'-丁二酸)]-20-喜树碱酯,化合物B2为20(S)-O - [-N-( 1'-氧基-2',2',6',6'-四甲基-1',2',5',6'-四氢吡啶酰胺)-4'-丙氨酸)]-20-喜树碱酯)。我们对化合物B1和B2进行了抗HIV活性检测。结果显示:化合物B2有较好的抗HIV-1和抗HIV-2活性,而化合物B1的抗HIV活性差。表明化合物B1的C-4’位-CH2被-NH取代,同时C-3’位-CH3修饰可能会提高其抗HIV活性。对化合物B2的抗HIV机制研究发现,化合物B2对慢性感染H9/HIV-1ⅢB细胞中病毒复制没有抑制活性、不能阻断H9/HIV-1ⅢB与正常细胞间的融合,对HIV-1蛋白酶、重组的HIV-1逆转录酶及整合酶没有抑制活性。化合物B2不具有选择性杀伤HIV-1ⅢB慢性感染的H9细胞系的作用。化合物B2抗HIV的作用机制还需进一步研究。 2、HIV/AIDS患者疱疹病毒感染状况及性病患者的HIV感染状况分析 疱疹病毒是AIDS患者合并感染的常见病原体。引起人类疾病的8种疱疹病毒与HIV感染及AIDS进展、机会性感染、恶性肿瘤密切相关。为了解HIV/AIDS患者人类8型疱疹病毒感染状况,我们检测了30例AIDS患者、40例HIV携带者及70例正常对照的液标本中8型疱疹病毒感染状况。采用ELISA法检测单纯疱疹病毒1型(HSV-1)、单纯疱疹病毒2型(HSV-2)、水痘-带状疱疹病毒(VZV)和巨细胞病毒(CMV);采用PCR法检测EB病毒(EBV)、疱疹病毒6型(HHV-6)、疱疹病毒7型(HHV-7)及疱疹病毒8型(HHV-8)。结果显示,HIV/AIDS患者中HSV-1、HSV-2、VZV、CMV、HHV-6、HHV-8 阳性率均高于健康体检者,其中AIDS患者VZV感染率与HIV携带者有显著性差异;在AIDS患者中多种疱疹病毒共感染普遍存在,必须重视HIV/AIDS患者合并疱疹病毒感染的防治。 性病可促进HIV的传播,了解性病患者的HIV感染状况及临床特征具有重要的意义。在自愿接受HIV咨询检测的基础上,对临床确诊的412例性病患者进行HIV-1/2抗体检测,并对其临床特征进行分析研究。结果显示412例性病患者的HIV检出率为2.9%。性病患者中检出HIV阳性率依次为:尖锐湿疣(6.2%)、生殖器疱疹(4.2%)、梅毒(3.4%)、淋病(1.5%)及非淋菌性尿道炎(1.0%)。83.3%合并感染HIV的性病患者存在多性伴,商业性行为普遍存在,安全套使用率极低现象。感染HIV的尖锐湿疣及生殖器疱疹患者以频繁复发为突出表现,1例合并感染HIV的梅毒患者半年即进展为神经梅毒。性病患者是HIV感染的重要高危人群,危险性行为是其感染HIV和其它性病的主要原因,应该加强性病患者的HIV检测。对临床上频繁复发的尖锐湿疣及生殖器疱疹患者、快速进展的梅毒患者应高度怀疑合并HIV感染的可能。
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对Egonol龙胆三糖苷及以Egonol衍生物对雌二醇生成活性及其相关机制进行了研究。发现Egonol龙胆三糖苷促雌二醇最高生成率在MCF-7、HepG2、ROS1728中分别为157% 、182.4%、226.8%(以空白组200μg/ml睾酮转换成E2值作为100%生成率)。活性的强弱可能与芳香化酶的组织特异性表达情况一致,说明Egonol龙胆三糖苷促雌二醇活性可能与芳香化酶有关。芳香化酶的组织特异性表达与特异性启动子有关系,Egonol龙胆三糖苷在各组织中皆有促雌二醇活性,说明该化合物不是通过调节该酶的基因表达而起作用。 在探究Egonol龙胆三糖苷及其衍生物是否介导cAMP-PKA途径从而影响芳香化酶的表达中,发现该系列化合物在HEK-293T细胞中对cAMP的影响非常弱小。在人HepG2细胞中显示了极强的提高cAMP的作用。而化合物对cAMP的作用与其促雌二醇活性强弱不呈正相关关系,对c AMP-PKA途径的激活可能与胞内雌激素有关。 Egonol龙胆三糖苷及其衍生物对HepG2细胞增殖影响显示,该系列化合物同雌二醇一样有相似的较弱促HepG2细胞增殖作用。而且存在一定剂量依赖性。在瞬时转染有ERE(雌激素作用元件)的HepG2中,Egonol龙胆三糖苷及其衍生物也显示了类似于雌二醇与ERE结合的作用,进一步提示Egonol龙胆三糖苷及其衍生物在HepG2细胞中具备雌激素样作用。 为研究Egonol龙胆三糖苷及其衍生物是否可能直接提高芳香化酶的活性,我们计划将芳香化酶从芳香化酶阳性细胞中克隆后表达到芳香化酶阴性的细胞中。在MCF-7细胞中以Oligo dT为引物合成的cDNA模板,和在ROS1728细胞中以Oligo dT及大鼠引物F链为引物合成的cDNA模板能成功扩增出与芳香化酶全长编码序列大小一致的片段。 Egonol衍生物在HepG2、ROS1728细胞中促雌二醇活性的实验表明,Egonol苯环上引入其它基团可以提高Egonol的活性。 从雌激素经典的基因组效应和非基因组效应两方面对雌激素信号转导研究进展进行了简单的综述。 The promoting effects of egonol gentiotrioside and egonol derivatives on the synthesis of estrogen E2 were studied. In vitro test, egonol gentiotrioside promoted the synthesis of estrogen E2 in MCF-7, HepG2,ROS1728 cell lines with mean yields of estrogen E2 57%,82.4% and 126.8%, higher than those of blank control at a concentration of 100 mg/ml. The difference of estrogen E2 synthesis promoting effects among the cell lines suggested tissue specificity. It is in accordance with tissue specific character of aromatase expression. The evidence implied that effect of egonol gentiotrioside on promoting the synthesis of estrogen E2 was related to the aromatase. Different expression levels of aromatase in different tissues are attributed to their specific promoters, but egonol gentiotrioside can promote the synthesis of estrogen E2, in many tissues,so the fact is controversary to the estimation that this compound regulates the aromatase on gene level. In order to investigate whether egonol gentiotrioside and its synthetic derivatives regulates aromatase activity through the cAMP-PKA signal pathway,we transfected the p CRE-Luc luciferase reporter gene into the HEK-293T cells and HepG2 cells. These compounds had weak activity in promoting the cAMP activity in HEK-293T cells but strong in HepG2 cells.The compounds’effect of promoting the cAMP may be related to their estrogenic activity in cells. The modified HepG2 cell proliferation assay was used to evaluate the estrogenic activity of egonol gentiotrioside and its derivatives. The weak estrogenic activity of egonol gentiotrioside and its derivatives at various concentrations expressed as proliferative effect relative to that of blank control was examined. We transfected the pERE-Luc luciferase reporter gene into the HepG2 cells. These compounds possessed significant activity on estrogen response element compared with the one treated with 10 n M estrogen E2. This evidence indicated that the estrogenic activity of egonol gentiotrioside and its derivatives. In order to investigate whether the egonol gentiotrioside and its derivatives can upregulate the activity of aromatase directly, The full-length of P450 aromatase cDNA encoding aromatase were amplified by using primer Oligo dT in MCF-7,and specific primer in ROS1728,respectively. The structure-activity relationship of Egonol in promoting the synthesis of E2 in HepG2 and ROS1728 cells indicated that introduction of some group on the basic sketon of egonol could improve the effect. The progress in research of signal pathway of estrogen in recent years was summarized.
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干扰素(IFNs)是最早发现的具有广泛用途的一类细胞因子,IFN-α通过JAK/STAT信号途径调控机体一系列生理和病理反应。至今尚未发现类干扰素的小分子。我们前期研究发现天然产物毛蕊异黄酮可激活干扰素诱导的JAK/STAT信号途径。为发现类干扰素小分子、获得小分子探针,本课题拟建立成熟的JAK/STAT信号途径的筛选模型,合成毛蕊异黄酮及其类似物,研究这些化合物的构效关系,进而尝试通过共价键标记生物素或香豆素来直接研究它们与相关受体的作用。 从异香草醛出发经7步合成反应得到了毛蕊异黄酮。采用平行合成策略得到异黄酮类化合物;采用分支式合成策略,以取代苯乙酸作为合成砌块,获得具有与异黄酮类似结构的香豆素、3-芳基喹诺酮。与分离得到的黄酮类化合物,构建了一个包括异黄酮、黄酮、香豆素、3-芳基喹诺酮在内的化合物库。 建立了包含IFN-α刺激反应元件 (ISRE)的荧光素酶报告基因体系,通过筛选化合物库中的化合物,发现异黄酮骨架为激活JAK/STAT信号途径必须结构、毛蕊异黄酮7-位酚羟基被取代后活性丧失。根据以上结果,对毛蕊异黄酮3′-位标记物的合成进行了初步尝试。 发现山茱萸科植物青荚叶(Helwingia japonica (Thunb.) Dietr.)有抑制蛋白酪氨酸磷酸酯酶1B(PTP1B)的活性。从其地上部分95%乙醇提取物的乙酸乙酯部分分离得到5个化合物,应用波谱方法及与已知品对照的手段鉴定它们为p-menth-2-en-1β, 4β, 8-triol (Z-1)、blumenol A (Z-2)、2′,3′,4′,5′,6′-五羟基查尔酮(Z-3)、洋芹素7-O-β-D-吡喃葡萄糖苷(Z-4)、木犀草素7-O-β-D-吡喃葡萄糖苷(Z-5). Interferons (IFNs) are one kind of cytokines with broad functions. IFN-α mediates series physiological and pathological changes of human body via JAK/STAT pathway. Untill now, no IFNs-like small molecules are discovered. In our preliminary experiment, the natural product calycosin has been observed to activate JAK/STAT pathway. Therefore, we establish a luciferase reporter gene system and synthesize calycosin and its analogues to reveal their structure-activity relationship (SAR). Besides, in order to prove that calycosin activates JAK/STAT pathway through IFN receptor, we attempted to tag it with biotin or coumarin by covalent bonding. Calycosin was synthesized from isovanillin via seven steps. Other isoflavones were obtained by parallel synthesis; coumarins and quinolones were prepared through divergent synthesis, using substituted phenylacetic acids as building blocks. Combing with natural flavones, a small molecule library was established. A luciferase reporter gene system, consisting of 5 copies of the ISRE (interferon-stimulated response element), was used for screening of small molecules from that library. We found that the core-structure of isoflavone was necessary, and if the 7-OH is substituted, the activity slumps. According to our observation, we tried to tag biotin or coumarin at 3′-OH of calycosin. The 95% ethanol extract of the aerial parts of Helwingia japonica (Thunb.) Dietr. showed protein tyrosine phosphatase 1B (PTP1B) inhibitory activity. Five compounds were isolated. On the basis of spectral data or by comparison with authentic samples, they were identified as p-menth-2-en-1β,4β,8-triol (1), blumenol A (2), 2′,3′,4′,5′,6′-pentahydroxychalcone (3), apigenin 7-O-β-D-glucopyranoside (4), and luteolin 7-O-β-D-glucopyranoside (5).
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本论文由三部分共四章组成。第一部分介绍丁香化学成分的研究成果,第二部分为升麻的化学成分研究,第三部分综述了环菠萝蜜烷三萜结构和活性关系的研究现状。 第一部分包括第一和第二章。第一章介绍了丁香(Eugenia caryophyllataThunb.)花蕾的化学成分和结构鉴定。采用正、反相硅胶柱层析等各种分离方法,从其乙醇提取物的乙酸乙酯萃取物和正丁醇萃取物中共分离出34 个化合物,它们的结构类型分属黄酮、三萜、鞣质等。其中1 个为新的酚苷类化合物,其结构经波谱分析鉴定为2-O-(6'-O-没食子酰基)-b-D-葡萄糖基苯甲酸甲酯(24),另外还有12 个化合物为首次从该植物中分离得到。第二章介绍了丁香挥发油的气相色谱- 质谱联用( GC-MS )和正丁醇萃取物的高效液相色谱- 质谱联用(HPLC-MS/MS)分析,尝试简单快速地检测丁香挥发油及极性部分的主要化学成分的方法。 第二部分为第三章。本章介绍了传统中药升麻(Cimicifuga foetida L.)根部乙醇提取物化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化方法和MS、NMR 等波谱解析技术,共分离鉴定了20 个化合物,主要为环菠萝蜜烷三萜,其中5 个新三萜化合物分别鉴定为cimicidol-3-one(38)、3'-O-乙酰基升麻苷H-1(41)、2'-O-乙酰基升麻苷H-1(42)、(3b,12b,16b)-12-乙酰氧-16,23-环氧-9,19-环羊毛甾烷-22-烯-24-酮3-O-b-D-吡喃木糖苷(44)和升麻碱(54)。新化合物54 为结构新颖的环菠萝蜜烷三萜皂苷生物碱,这是首个发现的具有环菠萝蜜烷三萜骨架的生物碱,也是从升麻属植物中发现的第一个三萜生物碱,它的结构通过多种波谱解析,特别是2D-NMR 的充分应用,并结合化学降解和反应得到证实。此外,还介绍了分离得到的一种具有明显抑制破骨细胞活性的化合物(QS29)的体外活性研究。 第三部分即第四章,综述了升麻属植物中环菠萝蜜烷三萜与其生物活性的构效关系研究现状。 This dissertation consists of three parts. In the first and the second parts, thechemical constituents from the flower buds of Eugenia caryophyllata and therhizomes of Cimicifuga foetida were reported. The third part is a review on astructure-activity relationship of the cycloartane triterpenoid from Cimicifuga species. The first part is composed of two chapters. The chapter 1 is about the isolationand identification of the chemical constituents from the flower buds of E.caryophyllata. A new phenolic glucoside gallate, methyl 2-O-(6’-O-galloyl)-b-D-glucopyranosylbenzoate (24), together with thirty-three known compounds has beenisolated from the ethanol extract of the flower buds of E. caryophyllata throughrepeated column chromatography on normal and reversed phase silica gel. Thestructure of the new compound was elucidated on the basis of spectral and chemicalevidence. Those kno wn compounds were belonged to flavone, triterpenoid, tannin andsome simple compounds. Among them, 12 compounds were isolated from the titleplant for the first time. The second chapter describes the capillary GC-MS analysis ofthe volatile components and the HPLC-MS/MS analysis of the polar constituents fromthe flower buds of E. caryophyllata, in order to detect the main constituents in thecrude extract rapidly and precisely. The third chapter is about the chemical constituents of the rhizomes C. foetida, atraditional Chinese medicine which was used as anti-inflammatory, analgesic andantipyretic agents. Our investigation of the bioactivities constituents of the rhizomesof C. foetida led to the isolation of five new cycloartane triterpenoids, which werecharacterized as cimicidol-3-one (38), 3'-O-acetyl cimicifugoside H-1 (41),2'-O-acetyl cimicifugoside H-1 (42), (3b,12b,16b)-12-acetoxy-16,23-epoxy-9,19-cyclolanost-22-ene-24-one 3-O-b-D-xylopyranoside (44) and cimicifugadine (54),along with fifteen known compounds through repeated column chromatography onnormal and reversed phase silica gel. Among them, 54 is a novel cycloartanealkaloid and first discovered as a new type alkaoid from nature. The structures ofthese compounds were elucidated on the basis of spectral and chemical evidence, andcimicidol-3-one was confirmed by X-ray crystallography analysis. Moreover, onecompound exhibited strong anti-osteoporosis activity in vitro experiment. The fourth part is a review on a structure-activity relationship analysis of thecycloartane triterpenoid from Cimicifuga species.
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川牛膝多糖(CP)是从传统中药川牛膝(Cyathula officinalis Kuan)中提取的一种活性多糖,现代药理研究表明川牛膝多糖是川牛膝许多生物活性的物质基础。本实验室前期进行了川牛膝多糖的提取、分离、结构鉴定及其部分活性研究,发现川牛膝中多糖含量非常高,在对川牛膝多糖活性的初步研究中也证实了其具有免疫调节作用。我们为了进一步了解其免疫调节活性,并为构效关系的研究奠定基础,对其进行了如下研究: 1. 通过体外毒性检测、淋巴细胞增殖实验、NK细胞杀伤活性和腹腔巨噬细胞吞噬中性红活性测定,发现川牛膝多糖在10~300μg/mL浓度范围内,对细胞无毒性作用;能够促进LPS诱导的B淋巴细胞增殖(P<0.01)、增强NK细胞杀伤活性(P<0.05)和PMΦ吞噬中性红活性(P<0.01),且随多糖浓度增高而增强;但其对ConA诱导的T淋巴细胞的增殖无促进作用(P>0.05)。 2. 通过正常小鼠体内淋巴细胞转化实验、迟发型变态反应分析、抗体生成细胞检测、碳粒廓清检测、腹腔巨噬细胞吞噬鸡红细胞活性和NK细胞活性测定,发现川牛膝多糖在适应性免疫方面能够促进SRBC免疫小鼠体内的抗体生成细胞的生成(P<0.01)和增强DNFB诱导的DTH(P<0.05),但对ConA诱导的脾淋巴细胞增殖无促进作用(P>0.05);在固有免疫方面能够提高小鼠碳粒廓清速率(P<0.05),PMΦ吞噬 CRBC 活性(P<0.01)和NK细胞杀伤活性(P<0.05)。同时还发现其对由环磷酰胺(Cy)引起的白细胞数下降具有很好的抑制作用(P<0.01)。 3. 为了获得结构明确、均一的保留活性的川牛膝多糖片段,为其作用机制、构效关系研究提供关键研究材料,我们开展了“保留免疫活性的最小片段”的分离制备的初步研究。建立并优化了川牛膝多糖的酸水解条件,发现在6%的样品浓度,0.025mol/L的硫酸浓度,65℃的水解温度,水解时间为8min的条件下可以得到一系列连续的多糖片段;采用Bio-Gel P2 分子筛柱层析分离得到5个级分,通过体外淋巴细胞增殖实验、NK细胞活性测定、腹腔巨噬细胞吞噬中性红实验发现其中的一个片段仍保留较强的免疫活性,并测得其分子量约为2057Da,为保留免疫活性的最小片段的进一步分离奠定了基础。 Cyathula officinalis Kuan is a commonly-used Traditional Chinese Medicine (TCM) with a wide range of pharmacological activities. Modern pharmacological researches showed the polysaccharide extracted from it (CP) is an important component for many bioactivities of this TCM. In the previous studies, we found CP showed significant immuno-regulative activities. In order to evaluate this activity systematically and lay foundations for revealling its immuno-regulative machanisms and the Structure -Function relationship, we carried out the following research works: 1. The in vitro immunoactivities of CP were evaluated by using normal mice immunocytes with respects to cytotoxicity, lymphocytes proliferation, NK activity and the ability of peritoneal macrophage phagocytizing neutral red. The polysaccharide showed no cytotoxicity below the concentration of 300 μg/mL, and could promote B lymphocytes proliferation (P<0.01), enhance NK activity (P<0.05) and the ability of peritoneal macrophage phagocytizing neutral red (P<0.01) at the concentration of 10-300 μg/mL. The above effects were positively correlated with the concentration of the polysaccharides. But it could not promote T lymphocytes proliferation (P>0.05). 2. The in vivo immunoactivities of CP were observed on normal mice through the following indices: splenic lymphocyte transformation efficiency, delayed-type allergy, antibody-forming cells activity (AFC), rate of carbon clearance, rate of peritoneal macrophage phagocytizing chicken red blood cell (CRBC) and NK activity, and its influence on the decline of the mouse leucocyte count induced by Cy. The polysaccharide at medium-dose enhanced delayed-type allergy (P<0.05)and NK activity(P<0.05) and increased the rate of carbon clearance(P<0.05), AFC activity(P<0.01) and the rate of peritoneal macrophage phagocytizing CRBC(P<0.01). The polysaccharides also effectively resisted the decline of the mouse leucocyte count induced by Cy(P<0.01). However, it couldn’t increase the splenic lymphocyte transformation efficiency(P>0.05). 3. Attempting to isolate and prepare the minimal fragments retaining activity with identical structure for further studying on immuno-regulative mechanism and Structure-Function relationship, we carried out the study on hydrolysis of CP, isolation of hydrolysed fragments, and the activity evaluation of the isolated fragments. CP with concentration of 6% was hydrolysed at 65℃ for 8 min with sulfuric acid of 0.025 mol/L,then the hydrolysate was separated using Bio-Gel P2 chromatography, 5 portions of fragments were obtained. The immunoactivities of these fragments were evaluated by using normal mice immunocytes with respect to lymphocytes proliferation, NK activity and ability of peritoneal macrophage phagocytizing neutral red. One fragment with relative molecular mass of 2057Da was found retaining immunoactivity.
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One-pot reduction of 9,10-diaryl-9,10-dihydrophenanthrene-9,10-diols to 9,10-diarylphenanthrenes was achieved with Zn/H+ in acetic acid. Accordingly, various novel phenanthrenes and polyphenanthrenes with efficient blue emission were easily synthesized.
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p21(Waf1/Cip1), best known as a broad-specificity inhibitor of cyclin/cyclin-dependent kinase complexes, can interact with various target proteins, and this ability relies on its structural plasticity. Therefore, studies on the structural properties of p(21) are very important to understand its structure-function relationship. However, detailed studies on its secondary structure and biophysical properties have been comparatively sparse. A human p(21) gene was cloned into the temperature expression vector pBV220 and transformed into Escherichia coli strain JM109.
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The synthesis, thermal and emission properties of an electrophosphorescent platinum(II) metallopolyyne polymer consisting of 9-butylcarbazole-2,7-diyl spacer P1 are described. The optical and electronic properties of P1 are compared to their molecular diplatinum(II) and digold(I) model complexes. The photophysical properties of P1 are somehow analogous to its 2,7-fluorene-linked congener but differs significantly from that for the 3,6-carbazole derivative. Its optical band gap is notably reduced as compared to that for the 3,6-carbazole analog. Multi-layer polymer light-emitting diodes (PLEDs) were fabricated with P1 as the emitting layer which gave a strong green-yellow electrophosphorescence. The best PLED can reach the maximum current efficiency of 4.7 cd . A(-1) at 5 wt.-% doping level, corresponding to an external quantum efficiency of 1.5%. This represents the first literature example of efficient PLEDs exhibiting pure triplet emission under electrical excitation for metallopolyynes without the concomitant singlet emission.