3′-大豆甙元磺酸钠的电化学行为及应用研究

采用线性扫描伏安法、循环伏安法和常规脉冲伏安法电化学手段详细研究了改性药物 3′ 大豆甙元磺酸钠 ( 3′ daidzeinsulfonicsodium ,Dss)在pH 1 0～ 6 2的水溶液中的电化学行为 .在不同pH范围内得到了Dss的三个还原波 .研究证实 ,在pH <3 2条件下所获得的Pc1,Pc2 波分别为质子化的Dss的单电子不可逆吸附还原波及还原中间体自由基的单电子单质子不可逆吸附还原波 ;在 3 2 相似文献   

两种新型水溶性异黄酮衍生物的合成与抗氧化活性

合成了未见文献报道的水溶性的3'-磺酸钠-4',7-二羧甲氧基异黄酮(L1)和3'-磺酸钠-4'-羟基-7-羧甲氧基异黄酮(L2), 采用IR, UV, ¹H NMR和元素分析对其结构进行了表征, 利用荧光光谱法研究了它们和母体大豆甙元(D)对羟基自由基的清除活性, 用紫外光谱法研究了其对超氧阴离子自由基和1,1-二苯基-2-苦肼基自由基(1,1-diphenyl-2-picrylhydrazyl free radical, 简称DPPH)的清除活性; 并采用量子化学AM1方法在全几何构型优化的基础上进行了电荷布居分析, 计算了它们抽氢反应的生成热(∆H_f), 从而从理论上探讨了目标化合物清除羟基自由基的活性. 实验结果表明本文合成的两种水溶性化合物清除超氧阴离子自由基和DPPH自由基的活性要优于母体大豆甙元, 对于目标化合物清除羟基自由基的活性, 实验和理论结果都显示其清除活性要优于大豆甙元．     

大豆苷元磺化物的合成、晶体结构及活性研究

对大豆苷元进行结构修饰和改性,利用磺化反应合成出强水溶性异黄酮新化合物大豆苷元磺酸钠,采用IR,MS和单晶X射线衍射法对其进行了表征和晶体结构测定,大豆苷元磺酸钠(C₃₀H₃₆Na₂O₂₃S₂)属三斜晶系,空间群P1,a=0.6948(14)nm,b=1.3277(3)nm,c=2.0401(4)nm,α=105.16(3)°,β=90.75(3)°,γ=92.73(3)°,V=1.8138(6)nm³,Z=2,μ=0.266mm^-1,F(000)=908,大豆苷元磺酸钠的晶体结构中包含大豆苷元磺化物异构体4′,7-二羟基异黄酮-3′-磺酸钠和4′,7-二羟基异黄酮-5′-磺酸钠及9分子水,配位水氧原子与钠离子配位在晶体内部形成一维聚合钠离子直链,该钠离子链将两种大豆苷元磺酸钠异构体及分子水联结在一起,形成空间网状结构,对于大豆苷元磺酸钠晶体结构的形成和稳定起了重要的作用,生理活性实验结果表明,大豆苷元磺酸钠的抗缺氧缺血作用明显优于大豆苷元.     

荧光光谱法研究大豆甙元与牛血清白蛋白的相互作用

采用荧光光谱技术研究了大豆甙元与牛血清白蛋白(BSA)的相互作用.研究结果表明:290 K、303 K、310K、315 K温度下大豆甙元对BSA的猝灭速率常数Ksv随着温度升高逐渐降低,且均大于最大动态猝灭速率常数2×1010 L·mol -1·s-1,表明大豆甙元对BSA的荧光猝灭属静态猝灭过程.根据F(o)rst...     

两种含氮类大豆苷元衍生物对人体红细胞的抗溶血作用

合成了2种含氮类大豆苷元衍生物,4,7-二（（甘氨酸钠）羰基）甲氧基异黄酮（L1）和4'',7-二（肼羰基）甲氧基异黄酮（L2）并用元素分析、红外光谱和核磁共振氢谱对其进行了表征。研究了大豆苷元衍生物的抗氧化性能,评价了其对自由基、超氧阴离子自由基的吸附能力,以及对人体血红细胞抗氧化损伤的保护作用。实验结果表明,大豆苷元衍生物在生理pH条件下的抗氧化活性优于维生素C,特别是在清除羟自由基和抑制人血红细胞溶血方面,大豆苷元衍生物抗氧化能力表现更为突出。大豆苷元衍生物的羟自由基清除活性IC₅₀值是维生素C的104倍。     

具有双螺旋链的新型镉(II)大豆甙元衍生物配位聚合物[Cd(L)(H_2O)_3]·2H_2O的合成与晶体结构研究

合成新型大豆甙元衍生物Cd(II)配合物[Cd(L)(H2O)3]·2H2O(H2L=3'-磺酸钠-4'-羟基-7-羧甲基异黄酮),采用单晶X射线衍射、元素分析和IR对其进行表征.该配合物属单斜晶系,空间群为P21/a,晶胞参数a=1.3691(3)nm,b=0.72157(16)nm,c=2.0163(5)nm,α=90°,β=93.501(4)°,γ=90°,V=1.9882(8)nm3,Mr=592.79,Z=4,Dc=1.980g·cm-3,F(000)=1192,μ=1.283mm-1,R1=0.0387,wR2=0.1224.X射线单晶衍射分析结果表明,该单晶中Cd(II)为六配位,它除了与配体L中羧基和磺酸基上的氧原子配位外,还与溶剂中的3个水分子发生配位,形成了以Cd(II)为中心的八面体配位构型.该晶体结构中存在着平行于b轴的双螺旋链,左手螺旋Cd-L链和右手螺旋Cd-L链的交替排列构成了二维层状结构.由于配位水和晶格水以及配体中CO2,SO3,O,CO,OH等的存在,该晶体中存在着丰富而复杂的氢键,二维层状结构之间依靠这些复杂的氢键作用形成三维超分子结构.     

3’-大豆甙元磺酸钠的电化学行为及应用研究

采用线性扫描伏安法、循环伏安法和常规脉冲伏安法电化学手段详细研究了改 性药物3’-大豆甙元磺酸钠(3’-daidzein sulfonic sodium,Dss)在pHl．0—6． 2的水溶液中的电化学行为.在不同pH范围内得到了Das的三个还原波．研究证实， 在pH＜3．2条件下所获得的Pcl，Pc2波分别为质子化的Dss的单电子不可逆吸附还 原波及还原中间体自由基的单电子单质子不可逆吸附还原波；在3．2＜pH＜6.2条 件下所获得的Pc3波，属于Dss后随质子化的单电子不可逆吸附还原波，而还原中间 体自由基的单电子波被氢波掩盖．测得在单分子层饱和吸附的条件下，每一个Dss 分子所占汞电极面积为0.664nm^2.此外，通过邻苯三酚自氧化产生活性氧自由基再 还原，对Dss清除活性氧自由基能力进行了研究，从电化学角度对其药理机制进行 了探讨，研究证实Dss具有较强的抗氧化性，是一种有效的活性氧自由基清除剂．     

四种黄酮类化合物与牛血清白蛋白相互作用的光谱分析

在人体生理pH条件下,利用紫外吸收光谱和荧光光谱研究了槲皮素(QUE)、大豆甙元(DAI)、4′,7-二甲氧基-3′-异黄酮磺酸钠(DISS)和3′-大豆甙元磺酸钠(DSS)四种黄酮类化合物与牛血清白蛋白(BSA)的相互作用,结合反应机理对其进行了初步探讨;并计算了结合位点数和结合常数.紫外吸收光谱分析结果表明,在pH=7.4条件下,黄酮类化合物中疏水性的苯环与BSA疏水腔中的氨基酸残基发生作用,从而导致药物分子的吸收峰红移,用Scatchard拟合法可求得DAI及DSS与BSA的结合常数.荧光光谱分析结果表明,BSA对DAI、DISS和DSS均有明显的敏化增强效应,计算得到的增强速率常数分别为1.39×1011,7.72×1011和1.93×1012L·s-1·mol-1,并可求得结合位点数和结合常数.     

线性扫描伏安法研究大豆甙元与牛血清白蛋白的相互作用

采用线性扫描伏安法研究了大豆甙元与牛血清白蛋白(BSA)之间的相互作用;探讨了缓冲体系、pH、反应时间、反应温度、扫描速率等对相互作用的影响.结果表明,在pH为7.4的B-R缓冲溶液中,大豆甙元与BSA在相互作用20min后形成1∶1型的单一的非电活性超分子化合物,两者的结合常数β=8.29×105 L·mol-1,转移系数α=0.367 9,表观电子传递速率常数ks为1.39s-1.     

乙基罗丹明B与大豆甙的显色反应及其应用研究

在 p H1 0 .5的 NH3- NH4 Cl缓冲溶液中 ,在聚乙烯醇存在下 ,乙基罗丹明 B与大豆甙形成 1∶ 1有色缔合物。其最大吸收波长为 5 65 nm,表观摩尔吸光系数为2 .0 1× 1 0 4 L· mol- 1· cm- 1,大豆甙在 1 .6～ 6.2 mg/L范围内符合比耳定律。方法用于大豆提取液中大豆异黄酮甙的测定 ,结果满意     

PHOTOSENSITIZING EFFECTS OF HEMATOPORPHYRIN DERIVATIVE IMMOBILIZED ON SEPHAROSE

Abstract— The cytotoxicity that ensues following photosensitization by hematoporphyrin derivative (Hpd) is attributed to production of singlet oxygen. Many of the cellular end points reported to be affected are localized to membranes, hydrophobic environments conducive to partitioning of hydrophobic porphyrins in Hpd. In order to test the hypothesis that efficacy of Hpd-induced photosensitization is enhanced by its ability to freely enter cells or subcellular organelles, we immobilized Hpd on a sepharose support. This immobilized reagent was found to produce ¹O₂ when photoradiated, in yields similar to those observed for Hpd in solution, as evidenced by the bleaching of p -nitrosodimethylaniline in the presence of imidazole. The immobilized Hpd was capable of photosensitizing, i.e. inhibit, cytochrome c oxidase activity in intact mitochondrial membranes and in aqueous solution. However, enzymes located on the interior of mitochondrial membranes (F₀F₁ ATP synthase and succinate dehydrogenase), in the mitochondrial matrix (malate dehydrogenase), or on the inside of the plasma membrane, (Na++ K+)- ATPase, were unaffected by immobilized Hpd plus photoradiation compared to free Hpd. The results suggest that photosensitization by Hpd most likely arises from entry of the photosensitizer into the biological membrane, although proteins on the exterior membrane surface may be susceptible to damage by ¹O₂ produced in proximity to their location.     

EFFECT OF HEMATOPORPHYRIN DERIVATIVE ON HEMATOLOGICAL PARAMETERS IN RATS

Abstract— Wistar rats were injected with hematoporphyrin derivative (Hpd) intraperitoneally and kept in the dark. Rats were sacrificed 2, 24, 48 and 72 h after injection. It was observed that Hpd in the dark did not affect the hemoglobin content and number of erythrocytes, while the leukocyte count was increased and blood pH decreased. Blood levels of glucose and lactate were increased significantly. Because the food intake was similar in all the groups, glycogenolysis was suspected to be the source of increased glucose levels in blood. However, a significant increase in the glycogen content of the livers of Hpd-treated rats was observed, which rules out glycogenolysis. Hyperglycemia may result due to a number of reasons such as stimulation of the central nervous pathways innervating the liver and adrenal medulla, excessive glucogenesis in liver from glycogen and noncarbohydrate sources, emotional stress, anesthesia and hormonal effects. The present study rules out hyperglycemia due to anesthesia and glucogenesis in the liver. Maintenance of blood glucose levels is a highly complex mechanism. Further investigations to understand these mechanisms are in progress.     

RHEOLOGICAL STUDY ON HYALURONIC ACID AND ITS DERIVATIVE SOLUTIONS

ABSTRACT

Rheological measurements were performed on Hyaluronic acid (HA) and its derivative solutions to evaluate steady flow viscosity and dynamics response with the aim to correlate the materials properties to the concentration, molecular weight and chemical structure. At low molecular weight and concentration, the HA solutions behaved as viscous liquid, whereas a soft-gel response was evident at higher molecular weight and concentration due to chains entanglement. Increasing the molecular weight was more effective than increasing concentration in promoting entanglement of molecular chains of HA. Comparing the behavior of HA solutions with that of Hyaluronic acid derivatives, it is showed that it is possible to modulate the rheological properties of HA based solutions by chemical modification preserving the bio-compatibility of the materials. The results of the rheological analysis provide a valuable tool to properly design optimal substitutes for specific biomedical application.     

NMR STUDY ON THE MAJOR COMPONENTS IN HEMATOPORPHYRIN DERIVATIVE YHPD

The hematoporphyrin derivative YHPD, a China-made product, has been clinically used in photodynamic therapy of tumors as a good photosensitizing drug. The NMR study on the structure of its major components is reported here. In terms of high performance liquid chromatography (HPLC) four major components A, B, C and D were isolated. The NMR results showed that the component A is O-acetylhematoporphyrin, B and C are two isomers of vinyldeuteroporphyrin. The spectra of 2-dimensional homonuclear correlation NMR, 2-dimensional NOE (nuclear overhauser enhancement), ~(13)C-NMR and off-resonance as well as FAB (fast atom bombarding) mass spectrum of component D indicate that it is a protoporphyrin dimer linked by carbon-carbon bond. This finding may providea chemical basis for understanding the difference in biological activity between YHPD and other foreign commercial HPD, as well as the composition of clincally used alkali-treated HPD and its effective component.     

血卟啉衍生物光照产生超氧化物阴离子自由基的一些观察

用氮蓝四唑(NBT)、细胞色素C还原及DMPO自旋捕集技术等三种方法分别在磷酸缓冲液、甲醇及二甲基亚砜(DMSO)中,测定超氧化物阴离子自由基(O₂^-·)。并与核黄素光照及邻苯三酚自氧化等二种已知产生O₂^-·系统相比较。结果表明:血卟啉衍生物光敏反应原初过程O₂^-·产率很低,水及DMSO等溶剂对OT的测定均有影响。     

WAVELENGTH DEPENDENCE OF HEMATOPORPHYRIN DERIVATIVE PHOTODYNAMIC TREATMENT EFFECTS ON RAT EARS

The in vivo wavelength dependence of hematoporphyrin derivative (HpD) photodynamic treatment (PDT) has been studied. Ears of 136 rats were treated at six red and four blue-green laser wavelengths (615-635, 488-514.5 nm). Hematoporphyrin derivative was administered intraperitoneally (15 mg/kg) and 24 h later both ears were irradiated, at different wavelengths, for t = 6.5, 10 or 15 min at 60 mW/cm2. Four parameters (thickness, average erythema, eschar and loss of tissue) were quantified and a combined score (CS) of effects was established statistically. The maximum combined score during follow-up was taken as a measure for the biological effect. The light distribution in rat ears during irradiation with red and blue-green light was estimated from in vivo measurements and the transport theory. Statistical analysis of the combined score data yielded values for the relative biological effectiveness (RBE). Relative biological effectiveness maxima occurred at 501.7 and 625 nm. Analyzing erythema and loss of tissue separately yielded maxima at the same wavelengths. Quantitative agreement between the latter two sets of relative biological effectiveness values was obtained only when they were referred to the actual light energy fluence in tissue, rather than to the incident fluence. These relative biological effectiveness values are about 2.3 at 501.7 nm and 1.35 at 625 nm, taking relative biological effectiveness = 1 at 630 nm.     

酞菁锌衍生物L-B膜的光电性能研究

用L-B膜方法在SnO₂电极上修饰了不同链长烷氧基取代的酞菁锌化合物(ZnPc C_nH_2n+1,n=3,9,12,16),分别研究了它们单分子膜成膜性能和转移性能,并测定了修饰在SnO₂电极上的单多层分子膜的光电性能和吸收光谱。研究结果指出链短的取代基即异丙氧基取代的酞菁锌(ZnPcC₃H₇(i))具有较高的转移比及较好的光电性能。     

苯衍生物二阶非线性光学性质的量子化学研究

本文采用引入外场微扰的CNDO/S—CI方法,计算了一系列苯衍生物的分子二阶非线性光学系数,探讨了取代基的电子性质、取代位置及取代基数目对分子二阶非线性光学系数的影响.结果表明;取代基的供电能力越强,分子的二阶非线性光学系数越大.D,A对位二取代苯和1—D,2.4—A,A三取代苯具有较高的非线性光学效应,苯衍生物中取代基数目为3时分子具有最佳的非线性光学效应.文中还对上述结论给出了初步的理论解释.     

PHOTODYNAMIC EFFECTS ON CELLS IN VITRO EXPOSED TO HEMATOPORPHYRIN DERIVATIVE and LIGHT

Abstract Several effects of hematoporphyrin derivative (HpD) and light on NHIK 3025 cells in vitro were studied. The treatment resulted in a partly repairable reduction of the rate of thymidine incorporation into DNA, a division delay, a reduced rate of protein synthesis, a reduced rate of active cellular uptake of α-aminoisobutyrate, a reduction in the colony-forming ability and an increased permeability of the cell membrane to chromate. Thymidine incorporation was by far the most sensitive parameter studied. However, comparison of the photodynamic effects after 1 and 18 h incubation with HpD prior to irradiation indicated that neither the reduced rate of DNA synthesis nor any of the other observed effects was the main primary cause of cell inactivation under all conditions. Several of the effects, such as increased permeability of the cell membrane to chromate, reduction in the rate of protein synthesis and reduction in the rate of repair of the damage to the mechanism of DNA synthesis, were clearly of secondary nature. When seen in relation to cellular survival, membrane damage was more important after short incubation times with HpD than after long incubation times.     

阳离子交换柱分离-导数光度法测定原油中钒

以 5Br PADAP为显色剂 ,用阳离子交换柱分离干扰离子 ,在波长 6 30nm采用一阶导数光度法测定原油中钒 ,方法灵敏度高 ,摩尔吸光系数为 3.0× 10 5L·mol- 1·cm- 1,较其它光度法测定钒的摩尔吸光系数提高 1～ 2个数量级。对实际样品进行分析并做加标回收试验 ,钒的回收率在97.5 %～ 10 4 .0 %。与ICP AES方法进行对照试验 ,结果相吻合。