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1.
采用相溶解度法,通过测定丹皮酚在不同温度不同浓度的β-环糊精(β-CD)、羟丙基-β-环糊精(HP-β-CD)、羟乙基-β-环糊精(HE-β-CD)、取代度为4的磺丁基醚-β-环糊精(SBE4-β-CD)以及取代度为7的磺丁基醚-β-环糊精(SBE7-β-CD)中的溶解度,绘制相溶解度曲线,丹皮酚的溶解度均随5种环糊精浓度的增加而成线性增加,相溶解度曲线为AL型,说明丹皮酚与环糊精以1∶1包合,实验结果表明,5种环糊精对丹皮酚均有增溶作用且SBE7-β-CD的增溶效果最佳.  相似文献   

2.
相溶解度法研究羟丙基-β-环糊精对肉桂酸的增溶作用   总被引:2,自引:0,他引:2  
通过测定肉桂酸在不同浓度羟丙基-β-环糊精中的溶解度,绘制相溶解度曲线,得到相溶解度曲线为AL型,实验结果表明,羟丙基-β-环糊精对肉桂酸有较好的增溶作用,增溶效应为:邻羟基肉桂酸对羟基肉桂酸间羟基肉桂酸,为其药效的改变提供了理论依据.  相似文献   

3.
通过相溶解度法,测定1,2-二氨基蒽醌、1,4-二氨基蒽醌和1,8-二羟基蒽醌在不同温度、不同浓度的β-环糊精(β-CD)、羟丙基-β-环糊精(HP-β-CD)以及羟乙基-β-环糊精(HE-β-CD)中的溶解度,绘制相溶解度曲线,并进行回收率及稳定性实验.实验结果表明:1,2-二氨基蒽醌、1,4-二氨基蒽醌和1,8-二羟基蒽醌的溶解度均随3种环糊精浓度的增加而呈线性增加,相溶解度曲线为AL型,蒽醌与环糊精形成的包合物类型为1∶1型,3种环糊精对蒽醌均有增溶作用,增溶效应顺序为HP-β-CDHE-β-CDβ-CD,与HP-β-CD作用顺序为1,2-二氨基蒽醌1,4-二氨基蒽醌1,8-二羟基蒽醌.  相似文献   

4.
通过测定蛇床子素(OST)在不同浓度的β-环糊精(-βCD)、羟丙基-β-环糊精(HP--βCD)、甲基-β-环糊精(M--βCD)中的溶解度,绘制出蛇床子素的相溶解度曲线,得到蛇床子素在三种环糊精中的相溶解度曲线均为AL型,说明蛇床子素与环糊精以1∶1包合,其表观结合常数分别为296.0 L.mol-14、41.8 L.mol-1、397.9 L.mol-1。实验结果表明,羟丙基-β-环糊精、甲基-β-环糊精对蛇床子素的增溶作用要优于β-环糊精。  相似文献   

5.
相溶解度法研究羟丙基-β-环糊精对格列齐特的增溶效果   总被引:2,自引:0,他引:2  
通过测定格列齐特在不同浓度羟丙基-β-环糊精中的溶解度,绘制相溶解度曲线,得到相溶解度曲线为As型,由实验结果表明羟丙基-β-环糊精对格列齐特有较好的增溶作用,为其剂型的改变提供理论基础。  相似文献   

6.
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   

7.
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   

8.
β-环糊精衍生物对黄酮类药物的增溶作用   总被引:9,自引:0,他引:9  
相溶解度;β-环糊精衍生物对黄酮类药物的增溶作用  相似文献   

9.
采用相溶解度法研究了β-环糊精(β-CD),及其衍生物羟丙基-β-环糊精(HP-β-CD)、磺丁基醚-β-环糊精(SBE-β-CD)、单6-脱氧-氨基-β-环糊精(NH2-β-CD)和单6-脱氧-乙二胺-β-环糊精(en-β-CD)对灯盏花乙素的增溶作用,并测定了主-客体分子形成包合物的平衡常数。结果表明,当灯盏花乙素与上述5种环糊精形成可溶性包合物时,对应的相溶解度曲线均为AL型,说明其与环糊精的包合比均为1∶1;多种弱相互作用力协同作用于环糊精的包结配位过程,环糊精衍生物的取代基影响了主-客体配位能力。5种环糊精主体化合物对灯盏花乙素客体分子的增溶能力的大小为:en-β-CD>NH2-β-CD>HP-β-CD>SBE-β-CD>β-CD。  相似文献   

10.
抗抑郁化合物SIP15838和环糊精分子非共价复合物的研究   总被引:1,自引:0,他引:1  
报道了用电喷雾电离质谱(ESI-MS),并结合紫外分光光度法及溶解度实验,研究一种新型的具有自主知识产权的抗抑郁化合物SIPI5838与α-环糊精(CD)和β-环糊精(CD)分子生成的非共价复合物.质谱测量结果表明,在溶液中,SIPI5838分子可以与环糊精分子之间生成非共价复合物,且两者之间的配比关系为1:1.这些非共价复合物的形成可以显著地提高这种抗抑郁化合物在水溶液中的溶解度,使得它作为高效的口服或注射药物成为可能.另外,还用紫外分光光度法和溶解度实验对液相中非共价复合物的形成进行了辅助研究,这些结果均显示了非共价复合物的生成.根据溶解度实验结果,计算了SIPI5838和两种环糊精分子在液相中的生成常数.它们分别为SIPI5838-β-环糊精:1.83×103 mol-1·L,SIPI5838-α-环糊精:3.15×101mol-1·L.两种非共价复合物的稳定程度为β-环糊精-SIPI5838>α-环糊精-SIPI5838.  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   

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14.
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   

15.
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   

16.
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   

17.
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   

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.  相似文献   

19.
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   

20.
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   

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