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1.
以β-环糊精为包合材料,制备异虎耳草素-β-环糊精包合物,以提高异虎耳草素的水溶性。结果表明,包合是成功的;异虎耳草素用β-环糊精包合后在水中的溶解度比包合前提高60倍。  相似文献   

2.
闫金红  张翠萍  杨频 《化学学报》2006,64(7):652-656
采用相溶解度法研究了丹参酮 IIA在不同pH和不同摩尔浓度的羟丙基-β-环糊精水溶液中的溶解度及二者的包合常数; 采用热力学方法研究了温度对包合反应的影响, 计算了包合过程的熵变、焓变及自由能变化; 用分子模拟方法进一步证实了该包合物的形成; 用红外光谱对固体包合物进行了表征.  相似文献   

3.
制备并鉴定温江大蒜油环糊精包合物。以大蒜油的平均利用率和包合物产率为指标,通过正交实验考查大蒜油与环糊精的投料比、包合温度、包合时间对包合工艺的影响,得出最佳包合工艺:投料比1∶8、包合温度60℃、包合时间2 h,此时挥发油的平均利用率为62.3%,包合物收率为72.1%。使用薄层色谱法对包合物进行鉴定,结果显示大蒜油与环糊精包合后,没有显示与大蒜油有相同的斑点,而大蒜油与环糊精的混合物有相同斑点。  相似文献   

4.
茵陈、白术挥发油-β-环糊精包合物的制备工艺研究   总被引:1,自引:0,他引:1  
以挥发油的包合率和包合物收率为指标,考察制备茵陈、白术挥发油-β-环糊精(β-cyclodextrin,简称β-CD)包合物的饱和溶液法、研磨法、超声法,并采用正交设计优化研磨包合工艺,筛选出其最佳条件为:挥发油与β-CDA的投料比为1∶4,β-CD与加水量的比为1∶15倍,研磨时间40 min.该条件下的包合率为85.4%,包合物收得率为93.5%.结果表明,研磨法包合茵陈、白术挥发油的包合率和收得率较高,包合物性质稳定,而且包合前后挥发油成分一致.  相似文献   

5.
羟丙基-β-环糊精与丹参酮IIA包合作用的研究   总被引:3,自引:0,他引:3  
闫金红  张翠萍  杨频 《化学学报》2006,64(7):652-656
采用相溶解度法研究了丹参酮 IIA在不同pH和不同摩尔浓度的羟丙基-β-环糊精水溶液中的溶解度及二者的包合常数; 采用热力学方法研究了温度对包合反应的影响, 计算了包合过程的熵变、焓变及自由能变化; 用分子模拟方法进一步证实了该包合物的形成; 用红外光谱对固体包合物进行了表征.  相似文献   

6.
采用研磨法和蒸馏法制备了阿魏酸(Ferulic acid,FA)和华法林(Warfarin,W)与β-环糊精(β-CD)的二元包合物,并采用红外光谱、紫外光谱、差热分析、扫描电镜和X粉末衍射法对其进行了表征,并在生理条件下研究了包合物的抗凝血性质及其与人血清白蛋白(Human serum albumin,HSA)的相互作用.结果表明,包合物的水溶性(包和物的溶解度约为5 g/L,华法林和阿魏酸为难溶物)和抗凝血指标都优于阿魏酸和华法林.与HSA作用的光谱结果表明,包合物可与HSA相互结合,增强了药物的血溶性,通过生成包合物避免了药物阿魏酸被氧化而失去原有的药效作用.说明华法林和阿魏酸经医药载体β-CD包合后水溶性增大,疗效增强,与HSA结合后可以达到药物通过血液输送的目的.  相似文献   

7.
本文采用冷冻干燥法制备获得二丁基羟基甲苯(BHT)的羟丙基-β-环糊精包合物(HP-β-CD IC)、二甲基-β-环糊精包合物(DM-β-CD IC)和磺丁基-β-环糊精包合物(SBE-β-CD IC)。相溶解度法确定了二者形成化学计量比为1:1的包合模型;粉末X射线衍射、差示扫描量热、核磁共振氢谱及扫描电镜等技术给出其可能的结合模式,并通过AutoDock分子模拟对接理论研究佐证了实验结果的可靠性;实验结果证明,三种包合物稳定性顺序为SBE-β-CD/BHT ICDM-β-CD/BHT ICHP-β-CD/BHT IC,其中SBE-β-CD/BHT包合物增溶效果最显著。1,1-二苯基-2-苦肼基(DPPH)法考察BHT三种包合物抗氧化活性的结果是:三种包合物均表现出良好的清除效果,且与BHT相当。利用β-CD衍生物的包合技术改善BHT的水溶性,是一种拓展BHT应用领域的有效策略。  相似文献   

8.
采用饱和水溶液法制备了大豆苷元分别与两种氨基修饰β-环糊精(ACD) 即单-6-氨基-β-环糊精(NCD) 和单-6-乙二胺基-β-环糊精(ENCD) 的固体包合物,并获得最佳包合条件:大豆苷元与环糊精投料比为3∶1(n/n) ,搅拌时间为72 h,分别获得83%和67%的产率.利用X-射线粉末衍射和热重分析对其进行了表征,证实了两种包合物的形成.利用Job′s曲线法确定了主客体的包合比为1∶1,并利用荧光光谱滴定分析测得其包合稳定常数KS分别为899.2和203.8 L/mol.水溶性实验表明,通过与NCD和ENCD形成包合物,25℃下大豆苷元在水中的溶解度由原来的8.31 μg/mL增至15.2和13.2 mg/mL,分别提高了约1800和1500倍.  相似文献   

9.
有机溶液中C60与对叔丁基杯[8]芳烃间的包合作用   总被引:4,自引:0,他引:4  
何俊  赵媛媛  安绪武 《化学学报》1997,55(9):839-845
在本工作中, 我们测量了苯、甲苯及四氯化碳中: C60和对叔丁基杯[8]芳烃及共混合液的紫外可见吸收光谱, C60和对叔丁基杯[8]芳烃及其包合物的饱合溶解度, 及包合物的浓度积;推算了上述有机溶液中C60与对叔丁基杯[8]芳烃间包合反应的平衡常数及液相中真正以包合形式存在的包合物的溶解度; 讨论了上述溶剂中包合物的存在形式、沉淀机理及溶剂效应。  相似文献   

10.
相溶解度法测定β-环糊精-芦丁包合物的形成常数   总被引:8,自引:0,他引:8  
采用相溶解度法研究了β-环糊精和芦丁形成包合物的包合作用,测定了其形成常数。结果表明:芦丁分子被环糊精包合后溶解度增加,并将实验获得的包合形成常数与文献值作了比较,结果令人满意。  相似文献   

11.
利用手持技术改进测定乙醇分子结构实验   总被引:1,自引:0,他引:1  
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。  相似文献   

12.
13.
由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。  相似文献   

14.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

15.
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.  相似文献   

16.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

17.
实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。  相似文献   

18.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.  相似文献   

19.
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.  相似文献   

20.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

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