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1.
本文通过将抗癌活性化合物cis-[RuCl2(Me2SO)4]与L-组氨酸在乙醇溶液中或在溶剂热条件下反应,均得到了配合物[RuCl(Me2SO)2(L-His)](1).X-射线单晶结构分析表明该配合物的晶体属变形八面体,空间群P3121,a=b=14.0575(16)A,c=15.637(3)A,分子中含一个结晶水.该配合物中L-组氨酸配体分别通过氨基氮、咪唑氮、羧基氧与中心原子钌(Ⅱ)配位.  相似文献   

2.
徐息良  黄仲贤 《化学学报》1986,44(10):1005-1010
本文报道了L-苏氨酸同Cu(II),Zn(II),Fe(II),Mn(II),Ca(II),Mg(II),Ni(II),Cd(II)的二元及三元配合物的pH电位法研究.电位滴定数据是使用MINIQUAD和ESTA计算机程序处理的.在每个体系中确定了最佳配合物粒子模型,并测定了在生理条件下(温度为37±0.1℃离子强度为150mmol.dm^-3NaCl)的稳定常数.结果表明在铜配合物中Cu,Thr.His混配配合物是与Cu(His)~2^-同样重要的配合物,因此需要重新计算在血浆中铜在这些配合物中的分布.虽然苏氨酸可以看作为三齿配位体,但本工作的结果并无证据支持羟基参与配位,然而在Cd-The-His体系中,Cd.Thr.His同它的1:2母体二元配合物相比表现了显著的稳定性,这可能显示了不同的配位状况.但这一点有待于进一步证实.  相似文献   

3.
用pH电位法测定了在生理条件下(37℃,I=0.15mol/LNaCl)7-氧杂双环-[2,2,1]庚-5-烯-2,3-二羧酸(OHDA)与各种典型氮基酸和锌、铜生成三元混配配合物的生成常数.模拟计算表明,作为药物配体的OHDA确可影响体内复杂的低分子量金属配合物的平衡,并且扰乱体内锌的分布,改变各种含锌酶的活性和功能.  相似文献   

4.
三元配合物La[(C5H8NS2)3(C12H8N2)]生成反应的热动力学   总被引:1,自引:3,他引:1  
在无水乙醇中, 用吡咯烷二硫代氨基甲酸铵(APDTC)和1,10-邻二氮菲(phen)与LaCl3·3.94H2O作用,合成了未见文献报道的三元固态配合物, 确定它的组成为La[(C5H8NS2)3(C12H8N2)]. X粉末衍射说明它为一新相化合物. IR光谱说明配合物中La3 分别与3个APDTC的6个硫原子双齿配位, 同时与phen的两个氮原子双齿配位, 配位数为8. TG-DTG分析显示其热分解为一步生成1/2La2S3 3C. 用微量热计测定了298.15 K下水合氯化镧及两个配体在无水乙醇中的溶解焓, 两个配体醇溶液的混合焓及不同温度下标题化合物液相生成反应的焓变. 在实验和计算基础上, 得到了液相生成反应的热力学参数 (活化焓、活化熵和活化自由能)和动力学参数(速率常数、表观活化能、频率因子和反应级数), 通过合理的热化学循环, 求得了标题化合物的固相反应焓变.  相似文献   

5.
金属四氮大环配合物的合成及性能的研究对于探讨生理过程,人工模拟具有一定的意义,本文研究的一种四氮配位的大环配合物是含有吡啶基的十四元四氮配位的大环配合物(图1),关于此类配合物的合成工作始于1974年,最早由Goedken和Paryzek合成了Fe(Ⅱ)、Mg(Ⅱ)、Zn(Ⅱ)、Sc(Ⅲ)的这类配合物。  相似文献   

6.
Cu(Ⅱ)-家蚕丝素蛋白质配合物的配位结构和高次结构   总被引:4,自引:0,他引:4  
家蚕丝素蛋白质在不同pH条件下经均相和不均相配位反应制备了Cu(Ⅱ)-丝素配合物,用可见光谱、电子自旋共振波谱(ESR)、X射线衍射(XRD)研究了其配位结构和高次结构.在碱性条件下(pH=10.60),丝素肽链主链的4个氮原子螯合Cu(Ⅱ)生成具有近似平面四方Cu(N)4结构的配合物;而在酸性条件下(pH=4.30,5.88),主要是丝素肽链的侧(端)基羧酸根键合Cu(Ⅱ)生成Cu(Ⅱ)(-COO-)(H2O)3和Cu(Ⅱ)(-COO-)2型配合物.讨论和描述了不同条件下生成的Cu(Ⅱ)-丝素配合物的高次结构.  相似文献   

7.
本文通过将抗癌活性化合物cisRuCl2Me2SO4与L组氨酸在乙醇溶液中或在溶剂热条件下反应均得到了配合物RuClMe2SO2LHis1。X射线单晶结构分析表明该配合物的晶体属变形八面体,空间群P3121a=b=14.057516c=15.6373分子中含一个结晶水。该配合物中L组氨酸配体分别通过氨基氮、咪唑氮、羧基氧与中心原子钌配位。  相似文献   

8.
氨基酸席夫碱配合物的制备及性能研究进展   总被引:15,自引:0,他引:15  
研究表明,某些含有-N=CH-基团的有机化合物具有一定的抗癌作用,它与某些金属生成配合物后效果更加显著。氨基酸是组成酶和蛋白质的基本单元,与含活泼羰基的化合物形成含有多个强电负性配位原子的席夫碱,此类席夫碱具有较强的配位能力和多样的配位模式的优点,研究其与金属离子配位所形成配合物可以为研究抗肿瘤、抗癌药物提供信息。80年代以来,有不少关于研究过渡金属离子与氨基酸席夫碱配合物的合成和性质的报道,并进行了大量生物生理活性的研究旧剖。本文综述了近年来国内外有关氨基酸席夫碱配合物的制备及其性能应用。  相似文献   

9.
王鹏  李莹  杨文斌  赵静静 《无机化学学报》2012,28(11):2301-2305
以3,5-二羧基苯氧乙酸(H3L)为配体与醋酸镉在不同pH条件下获得了2个Cd(Ⅱ)配合物[Cd(H2L)2(H2O)4](1)、[Cd(HL)]n(2),通过红外、X-射线单晶衍射等检测手段对所合成的化合物进行了结构表征。测定结果表明,这2个配合物分别为配位分子和三维配位聚合物,其结构的形成与水热条件的pH值密切相关。该结果对以pH值控制配合物结构提供了研究基础。  相似文献   

10.
稀土与L-苯丙氨酸配合物的PH电位法及量热滴定法研究   总被引:4,自引:0,他引:4  
本文在25℃和0.15mol.dm^-^3(NaCl)离子强度下, 用pH电位法和量热滴定法测定了十五个稀土元素(Y和除Pm外的镧系元素)与L-苯丙氨酸1:1配合物的稳定常数及热力学函数。L-苯丙氨酸通过-CO^-~2和-NH~2与稀土离子配位, 生成较稳定的1:1配合物。配合物稳定性呈"四分组效应"。配合物稳定性顺序中Y的位置向轻稀土方向移动。体系的熵变是配位反应驱动力。离子的去水化在配位反应中起重要作用。  相似文献   

11.
Ionic liquids (ILs) have been extensively used in drug formulation and delivery as designer solvents and other components because of their inherent tunability and useful physicochemical and biopharmaceutical properties. ILs can be used to manage some of the operational and functional challenges of drug delivery, including drug solubility, permeability, formulation instability, and in vivo systemic toxicity, that are associated with conventional organic solvents/agents. Furthermore, ILs have been recognized as potential solvents to address the polymorphism, limited solubility, poor permeability, instability, and low bioavailability of crystalline drugs. In this account, we discuss the technological progress and strategies toward designing biocompatible ILs and explore potential biomedical applications, namely the solubilization of small and macromolecular drugs, the creation of active pharmaceutical ingredients, and the delivery of pharmaceuticals.  相似文献   

12.
Targeting acquired drug resistance represents the major challenge in the treatment of EGFR‐driven non‐small‐cell lung cancer (NSCLC). Herein, we describe the structure‐based design, synthesis, and biological evaluation of a novel class of covalent EGFR inhibitors that exhibit excellent inhibition of EGFR‐mutant drug‐resistant cells. Protein X‐ray crystallography combined with detailed kinetic studies led to a deeper understanding of the mode of inhibition of EGFR‐T790M and provided insight into the key principles for effective inhibition of the recently discovered tertiary mutation at EGFR‐C797S.  相似文献   

13.
14.
Despite enormous progress in the treatment of many malignancies, the development of cancer resistance is still an important reason for cancer chemotherapy failure. Increasing knowledge of cancers’ molecular complexity and mechanisms of their resistance to anticancer drugs, as well as extensive clinical experience, indicate that an effective fight against cancer requires a multidimensional approach. Multi-target chemotherapy may be achieved using drugs combination, co-delivery of medicines, or designing hybrid drugs. Hybrid drugs simultaneously targeting many points of signaling networks and various structures within a cancer cell have been extensively explored in recent years. The single hybrid agent can modulate multiple targets involved in cancer cell proliferation, possesses a simpler pharmacokinetic profile to reduce the possibility of drug interactions occurrence, and facilitates the process of drug development. Moreover, a single medication is expected to enhance patient compliance due to a less complicated treatment regimen, as well as a diminished number of adverse reactions and toxicity in comparison to a combination of drugs. As a consequence, many efforts have been made to design hybrid molecules of different chemical structures and functions as a means to circumvent drug resistance. The enormous number of studies in this field encouraged us to review the available literature and present selected research results highlighting the possible role of hybrid drugs in overcoming cancer drug resistance.  相似文献   

15.
胆汁酸为载体的肝靶向一氧化氮释放药物的设计与合成   总被引:1,自引:0,他引:1  
李美英  何新华  陶林  刘河  李宏武  仲伯华 《有机化学》2008,28(12):2170-2174
新型肝靶向一氧化氮释放药物对许多肝脏疾病具有较好的治疗作用. 以胆酸和熊去氧胆酸作为药物的载体, 以氨基酸作为联接子, 以氨基酸的α羧基模拟胆酸或熊去氧胆酸分子24位羧基的负电性, 最大限度地保持胆酸或熊去氧胆酸的结构特征, 通过酰胺键将载体与一氧化氮供体硝酸酯偶联, 设计并合成了一系列新型肝靶向一氧化氮释放偶合物, 其结构经元素分析, IR, 1H NMR和MS光谱分析确证. 利用四氯化碳及对乙酰氨基酚所致小鼠急性肝损伤模型研究化合物对小鼠急性肝损伤的修复作用.  相似文献   

16.
Because of the multi-functional characteristics and bioadaptability, cyclodextrin (CyD) is capable of alleviating the undesirable properties of drug molecules through the formation of inclusion complexes. This paper outlines the current application of natural and chemically modified CyDs in the various pharmaceutical formulations including peptide and protein drugs. Furthermore, potential use of CyD/drug conjugates in site-specific drug delivery is discussed.  相似文献   

17.
The chemical structure of end groups influenced the phase transition temperature of thermoresponsive polymers. We demonstrated a strategy for the preparation of the pH/thermo-responsive polymeric nanoparticles via subtle modification of end groups of thermoresponsive polymer segments with a carboxyl group and revealed its potential application for enhanced intracellular drug delivery. By developing a polymeric nanoparticle composed of poly(aliphatic ester) as the inner core and thermoresponsive polyphosphoester as the outer shell, we showed that end groups of thermoresponsive polyphosphoester segments modified by carboxyl groups exhibited a pH/thermo-responsive behavior due to the hydrophilic to hydrophobic transitions of the end groups in response to the pH. Moreover, by encapsulating doxorubicin into the hydrophobic core of such pH/thermo-responsive polymer nanoparticles, their intracellular delivery and cytotoxicity to wild-type and drug-resistant tumor cells were significantly enhanced through the phase-transition-dependent drug release that was triggered by endosomal/lysosomal pH. This novel strategy and the multi-responsive polymer nanoparticles achieved by the subtle chain-terminal modification of thermoresponsive polymers provide a smart platform for biomedical applications.  相似文献   

18.
Human ferritins are emerging platforms for non‐toxic protein‐based drug delivery, owing to their intrinsic or acquirable targeting abilities to cancer cells and hollow cage structures for drug loading. However, reliable strategies for high‐level drug encapsulation within ferritin cavities and prompt cellular drug release are still lacking. Ferritin nanocages were developed with partially opened hydrophobic channels, which provide stable routes for spontaneous and highly accumulated loading of FeII‐conjugated drugs as well as pH‐responsive rapid drug release at endoplasmic pH. Multiple cancer‐related compounds, such as doxorubicin, curcumin, and quercetin, were actively and heavily loaded onto the prepared nicked ferritin. Drugs on these minimally modified ferritins were effectively delivered inside cancer cells with high toxicity.  相似文献   

19.
药物脉冲释放系统   总被引:2,自引:0,他引:2  
药物脉冲释放体系由于其释药动力学符合生物机体的需要而备受关注,本文对各种药物脉冲释放系统,包括程序式药物脉冲释放系统及智能式药物脉冲释放系统进行综述。  相似文献   

20.
Poly(β amino ester) (PβAE) polymers have received growing attention in the literature, owing to their ease of synthesis, versatile co‐monomer selection, and highly tunable degradation kinetics. As such, they have shown extensive potential in many biomedical applications as well. In this work, it is demonstrated for the first time that PβAE polymers containing primary and secondary amine groups can undergo degradation by primary alcohols via transesterification mechanism. While this work emphasizes an important aspect of solvent compatibility of these networks, it also represents an interesting, simple mechanism for post synthesis drug incorporation, with riboflavin conjugation being demonstrated as a model compound. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2019–2026  相似文献   

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