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利用质谱仪,使用电喷雾离子源,分别研究了以α-环糊精、β-环糊精和产环糊精作为手性拆分剂对手性药物甲基麻黄碱的手性识别效应.实验结果表明,3种环糊精对甲基麻黄碱对映体均有较强的手性识别效应,Rchiral分别为2.43、3.51、4.52.研究了电压的变化对α-环糊精、β-环糊精和γ-环糊精的手性识别的影响,研究发现,在不同的电压下,这3种环糊精对甲基麻黄碱均有手性识别能力. 相似文献
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新型环糊精衍生物单6-O-苯基胺甲酰基-β-环糊精的合成及其在手性药物毛细管区带电泳拆分中的应用 总被引:6,自引:4,他引:6
合成了新型的环糊精衍生物单6-O-苯基胺甲酰基—β-环糊精,并对合成产物进行了表征。以新型环糊精衍生物为手性选择剂,考察了手性选择剂浓度、缓冲液PH值和浓度及有机溶质对8种手性药物对映体的毛细管电泳分离的影响。结果表明:手性选择剂浓度和缓冲液PH值是影响药物对映体分离的重要因素,有机溶质亦对分离有很大影响。单6-O-苯基胺甲酰基—β-环糊精能使所研究的8种手性药物中的5种达基线分离,3种达部分分离。而在同样条件下.β-环糊精仅能使上述药物中的菜心安达部分分离(及。=0.67),这说明我们合成的环糊精衍生物手性拆分能力要强于天然环糊精。我们还就单6-O-苯基胺甲酰基-β-环糊精对手性药物可能的拆分机理进行了探讨。 相似文献
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探讨了环糊精对美国西律对映体手性识别的机理,对毛细管电泳手性分离选择系数a值和环糊精包结常数的计算方法做了修正,计算了甲基化β环糊精与对映体形成包结络合物的稳定常数和手性分离过程中的热力学参数,并对由该方法计算的结果进行了分析,结果表明,环糊精对美西律对映体包结常数的大小顺序与它们的手性分离选择相相反,但是,手性分离过程中的焓变(△(△H)和熵变(△(△S))越大,手性分离选择性也越大,根据计算结 相似文献
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分别以2种天然环糊精(β、γ-环糊精)、2种常用的电中性环糊精衍生物(羟丙基-β-环糊精、二甲基-β-环糊精)和3种新型荷电环糊精衍生物(高取代磺酸基α、β、γ-环糊精)作为毛细管区带电泳手性添加剂,研究了环糊精的类型对6种手性药物对映体分离的影响.2种天然环糊精对所研究的手性药物均无手性识别能力,而环糊精经过衍生化后手性识别能力得到了很大的提髙,尤其是高取代磺酸基β-环糊精使6种手性药物均得到了基线分离.还考察了缓冲溶液的pH值和有机添加剂对手性分离的影响. 相似文献
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毛细管电泳在手性化合物分离中的应用 总被引:4,自引:0,他引:4
本文综述了近年来毛细管电泳在手性化合物分离中的应用情况。简要地总结和比较了手性配位体金属络合物、环糊精及其衍生物、开环多糖化合物、冠醚、大环化合物等5种典型的手性分子识别剂在毛细管电泳手性分离中的使用现状。 相似文献
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总结了手性逆流色谱的5个特点,系统地介绍了逆流色谱的手性分离以及高速逆流色谱手性分离中氨基酸衍生物、环糊精衍生物、手性有机酸、多糖衍生物、牛血清白蛋白等手性选择剂的应用。 相似文献
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Cyclodextrin (CD) derivatives are the most efficient and frequently used chiral selectors (CSs) in capillary electrophoresis (CE). There are situations when the use of a single CD as CS is not enough to obtain efficient chiral discrimination of the enantiomers; in these cases, sometimes this problem can be resolved using a dual CD system. The use of dual CD systems can often dramatically enhance enantioseparation selectivity and can be applied for the separation of many analytes of pharmaceutical interest for which enantioseparation by CE with another CS systems can be problematic. Usually in a dual CD system an anionic CD is used together with a neutral one, but there are situations when the use of a cationic CD with a neutral one or the use of two neutral CDs or even two ionized CDs can be an efficient solution. In the current review we present general aspects of the use of dual CD systems in the analysis of pharmaceutical substances. Several examples of applications of the use of dual CD systems in the analysis of pharmaceuticals are selected and discussed. Theoretical aspects regarding the separation of enantiomers through simultaneous interaction with the two CSs are also explained. Finally, advantages, disadvantages, potential and new direction in this chiral analysis field are highlighted. 相似文献
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Yuan Chen Lulu Fu Baobao Sun Cheng Qian Dr. Srikala Pangannaya Hong Zhu Prof. Jing Ma Prof. Juli Jiang Dr. Zhigang Ni Prof. Ruibing Wang Prof. Xiancai Lu Prof. Leyong Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(19):5890-5896
Chiral α-amino acids play critical roles in the metabolic process in nearly all life forms. So far, chiral recognition of α-amino acids has mainly focused on the determination of l /d enantiomers. Herein, selection of planar chiral conformations between water-soluble pillar[5]arene WP5 and pillar[6]arene WP6 was observed due to α-side chain or ethyl ester moieties of l -α-amino acid ethyl ester hydrochlorides binding with WP5 and WP6 , respectively. Therefore, α-side chain and ethyl ester moieties of l -α-amino acid ethyl ester hydrochlorides were recognized by observing the induced CD signal and its inversion. This is a rare example of being able to detect the chiral region around α-carbon of a chiral α-amino acid molecule. 相似文献
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In this paper, the enthalpy-entropy compensation effect in the enantiomeric separation by modified cyclodextrins (CD) and diamide chiral stationary phase (CSP) gas chromatography was investigated using the method of plotting △(△H) versus △(△G) rhm combined with t-test statistic analysis. The investigated racemates cover α-phenylethylamine and its analogs, 2-alkylamines, chiral acyclic alcohols, halogenated arylethanediol-1, 2-diperfluoropropionates, amino acid and its analogs, and two series of compounds containing chloro and bromo substituents. From the compensation analysis results, the effects of the diluent composition in the investigated chiral stationary phases, the size and the modified groups on investigated cyclodextrins, the derivatization methods and the groups attached to the stereocenters on enantiomeric separation mechanisms were all discussed. 相似文献
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目前环糊精(CD)手性固定相(CSP)的研究大多集中于对CD或桥联臂进行功能衍生引入更多作用位点以提升手性拆分能力,鲜有能够反映天然CD本征识别能力的CSP的研究报道,该文通过"巯基-烯"点击化学反应合成了结构明确可控的单(6-巯基-6-去氧)-β -环糊精手性固定相(CSP1),其最大限度地保留了天然CD的本征结构,且桥联臂无识别作用位点,固体核磁共振(13 C SSNMR)和红外光谱(FTIR)的表征结果证明了CSP1的成功制备,元素分析结果表明,与双键功能化硅胶相比,CSP1的C、H、N的百分含量均得到了提高,计算得出CSP1的表面CD固载量为0.82 μmol/m2。采用高效液相色谱反相模式对50多种手性对映体包括异(口恶)唑啉、手性交酯、手性酮、黄烷酮以及丹磺酰氨基酸等进行了手性拆分,充分考察了天然CD的本征手性识别能力,结果表明CD的本征识别能力比较有利于异(口恶)唑啉类样品中含有两个疏水苯环基团Ph-Ph类样品的分离,对于其他几类样品仅利于部分样品的分离。同时与前期制备的功能三唑桥联CD-CSP及咪唑嗡桥联CD-CSP在同一色谱条件下进行了结果比对,结果证明样品的分离过程除了与手性介质的结构有关外,还与样品分子的结构有很大关系,对桥联臂进行功能改性可提升对部分对映体的选择性,但同时会小幅损失CD的本征手性识别能力。对于环糊精本征识别能力易于分离的样品,在设计手性介质时,其桥联臂不需要任何官能团,这为CD固定相结构的设计提供了有益参考。 相似文献
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Hiroki Ishikawa Naohiro Uemura Rei Saito Prof. Yasushi Yoshida Prof. Takashi Mino Prof. Yoshio Kasashima Prof. Masami Sakamoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(41):9758-9763
Dynamic enantioselective crystallization enabled the chiral symmetry breaking of two spiropyrans and one spirooxazine. The three spiro compounds afforded racemic conglomerate crystals, and easily racemized in alcoholic solution without irradiation. Optically pure enantiomorphic crystals were obtained by vapor-diffusion crystallization or attrition-enhanced deracemization (Viedma ripening). Their absolute configurations were determined by single-crystal X-ray analysis and each enantiomorphic crystal was correlated with its solid-state circular dichroism (CD) spectrum. 相似文献
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毛细管电泳法手性拆分合成药物氨氯地平及其中间体 总被引:6,自引:0,他引:6
建立了毛细管电泳手性拆分氨氯地平药物中间体的方法 ,并同时拆分了氨氯地平。考察了不同手性拆分试剂对手性选择性的影响 ,其中羧甲基 β 环糊精 (CM β CD)能够给出满意的拆分结果。在以CM β CD为手性拆分试剂的基础上 ,还考察了各种因素诸如流动相的pH值、环糊精的浓度以及电压对分离的影响。最佳拆分条件为 :30mmol/L磷酸盐 +5 0mmol/LCM β CD(pH 6 12 )。在此条件下 ,药物中间体及氨氯地平的分离度分别为 1 5 5和 1 73,结果令人满意。 相似文献
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手性污染物对映体尽管具有相似的物理化学性质,但在环境中的吸附、转移、降解等过程往往存在一定差异。生态安全问题与人类健康密切相关,因此,对手性环境污染物进行对映体水平上的分离分析是十分重要的研究课题。目前,国内外对环境中的手性污染物已开展了相关研究,然而全面评述相关分析测定方法的新进展鲜有报道。本文主要对环境中手性污染物的种类以及近5年环境中手性污染物的分析检测技术如液相色谱-质谱联用法、气相色谱-质谱联用法、毛细管电泳法、超临界流体色谱-质谱联用法等进行了归纳、综述和展望,为后续手性污染物的分析检测提供依据和参考。 相似文献
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Hideo Tokuhisa Tamako Ogihara Yoshinobu Nagawa Kazuhisa Hiratani 《Journal of inclusion phenomena and macrocyclic chemistry》2001,39(3-4):347-352
Asymmetric crownophanes having a chiral binaphthyl unit and two phenolic hydroxyl groups were thermally synthesized from the corresponding macrocyclic ethers via tandem Claisen rearrangement. Circular dichroism (CD) spectroscopic studies and HPLC experiments confirmed that little racemization of these crownophanes occurred during the thermal rearrangement. The association constants for the interaction of the chiral crownophanes with the enantiomers of phenylethylamine, phenylglycinol, and phenylalaninol were determined by a 1H NMR titration method in CD2Cl2. As a result, the 27 membered crownophane has some chiral recognition for phenylglycinol. 相似文献
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研究了3, 5-二甲基苯基异氰酸酯对羟丙基-β-环糊精固定相的手性识别影响.通过异氰酸丙基三乙氧基硅烷作偶联剂,将羟丙基-β-环糊精键合到3-氨丙基硅烷化硅胶上,再用3, 5-二甲基苯基异氰酸酯对β-环糊精和硅胶其余羟基进行衍生化,制得一种新型的3, 5-二甲基苯基氨基甲酸酯全衍生化羟丙基-β-环糊精键合硅胶手性固定相.在反相色谱条件下,对9种手性药物进行了拆分,结果表明,3, 5-二甲基苯基氨基全衍生化固定相较之羟丙基-β-环糊精固定相有更好的分离效果. 相似文献