羧甲基聚合-β-环糊精在毛细管电泳中分离酪氨酸对映体

采用羧甲基聚合-β-环糊精为手性选择剂对酪氨酸对映体以毛细管区带电泳形式进行手性拆分。考察了手性选择剂浓度、背景电解质溶液pH值、柱温及分离电压对分离的影响。在优化的实验条件下,使酪氨酸对映得到了基线分离。     

天冬氨酸-β-环糊精在毛细管电泳中拆分手性药物罗格列酮

本文建立了一种快速、简单拆分手性药物"罗格列酮"的新方法。采用本实验室合成的天冬氨酸-β-环糊精为手性选择剂,在毛细管区带电泳中对罗格列酮进行拆分,通过优化影响实验的主要因素(手性选择剂浓度、缓冲溶液pH、柱温及分离电压),得到了使罗格列酮达到基线分离的最佳实验条件。     

2-O-（2-羟丁基）-β-环糊精在非水毛细管电泳中拆分手性药物的研究

以2—O-（2一羟丁基）-β-环糊精（HB-β-CD）为手性选择剂,对普萘洛尔、山茛菪碱、异丙嗪3种碱性手性药物进行非水毛细管电泳拆分。考察了有机溶剂、电解质、手性选择剂浓度以及pH值对分离度的影响。研究结果表明：普萘洛尔、山莨菪碱和异丙嚷3种碱性手性药物全部达到基线分离。可见HB-β-CD在碱性药物拆分方面具有特殊能力,为碱性手性药物的拆分提供了一种准确、简便的分析方法。     

羟丙哌嗪手性拆分的HPCE新方法

以组氨酸-β-环糊精（β-CD-E_2）衍生物作为手性选择剂,利用原位聚合反应制得新型β-CD衍生物手性高效毛细管电泳（HPCE）整体柱,将其应用于手性药物羟丙哌嗪的消旋体拆分。分别探究了不同缓冲体系的洗脱能力、缓冲液pH对分离的影响以及羟丙哌嗪手性拆分的线性范围。结果表明,在最佳条件下,羟丙哌嗪对映体在β-CD-E_2整体柱上能得到较好拆分,分离度Rs达到40.52,且羟丙哌嗪浓度在9.8×10~(-6)～2.0×10~(-5)mol/L范围内与对映体峰高、峰面积具有一定的线性关系。此工作将β-CD-E_2作为HPCE固定相,为手性药物羟丙哌嗪建立了一种新的分离分析体系。     

新型高效毛细管电泳整体柱拆分拉米夫定

以双[-6-氧-(-3-间硝基苯磺酰基-丁二酸-1,4-单酯-4-)-]-β-CD(β-CD-F2)作为手性选择剂,利用原位聚合反应制得新型β-环糊精衍生物手性高效毛细管电泳(HPCE)整体柱。对核苷类似物逆转录酶抑制剂拉米夫定外消旋体混合物进行手性拆分,通过探究p H值、工作电压等条件对拆分的影响,优化拆分条件,结果表明,在最佳条件下,拉米夫定两对映体分离度Rs达到22.02,初步建立了一种新型拉米夫定对映体的HPCE拆分分析方法。     

羧甲基-β-环糊精的改性及其在毛细管电泳中的应用

针对羧甲基-β-环糊精(CM-β-CD)作为手性选择剂在毛细管电泳分离手性药物中存在着分离度不大、峰形不对称、毛细管壁的吸附、基线不稳等问题,通过CM-β-CD与1-丁基-3-甲基咪唑氯离子液体([Bmim]Cl)进行阳离子交换反应,得到一种类似于离子液体的β-CD衍生物([Bmim](β-CD-OCH2COO)),并将其在毛细管电泳中作为缓冲液的手性添加剂分离盐酸布比卡因、扑尔敏,与CM-β-CD作为手性添加剂相比,分离度提高,峰型得到了改善,基线基本稳定,获得了较为理想的分离效果。     

基于离子液体辅助的毛细管电泳法手性拆分阿替洛尔对映异构体

建立了以羧甲基-β-环糊精(CM-β-CD)为手性选择剂,以非手性离子液体溴化1-十二烷基-3-甲基咪唑(C12MIm Br)为手性分离添加剂的毛细管电泳分离阿替洛尔对映异构体的方法。实验详细考察了运行缓冲溶液p H值与浓度、手性选择剂用量、离子液体用量、分离电压等影响手性拆分的重要因素。同时,与未添加离子液体的毛细管电泳分离情况进行了对比,发现离子液体对手性药物的拆分有协同作用,不仅能够增加对映异构体的分离度,还能有效地抑制毛细管内壁对样品分子的吸附作用,改善峰形。     

新型高效毛细管电泳手性整体柱拆分普罗帕酮

以双-(6-氧-间硝基苯磺酰基)-β-环糊精作为手性选择剂,利用原位聚合反应制得双-(6-氧-间硝基苯磺酰基)-β-环糊精手性高效毛细管电泳(HPCE)整体柱,采用HPCE法考察该柱对手性药物普罗帕酮(Propafenone)的手性拆分能力,并对其拆分条件进行优化。结果表明:在最佳条件下,普罗帕酮两对映体分离度RS达到52.82,建立了一种有效的普罗帕酮两对映体分离分析新方法。     

羧甲基-β-环糊精和离子液体联用拆分西酞普兰对映体

建立以羧甲基-β-环糊精(CM-β-CD)和离子液体三甲基羟乙基双三氟甲磺酰亚胺盐(HOEt N1,1,1NTf2)共同作为手性选择剂,用于分离西酞普兰对映体的毛细管电泳法。采用未涂层熔融石英毛细管柱,考察CM-β-CD的质量浓度、HOEt N1,1,1NTf2的浓度、背景缓冲液的浓度及其p H和分离电压对拆分西酞普兰对映体的影响。在20 mmol/L磷酸盐缓冲液(p H 6.8)中添加15 g/L CM-β-CD和40 mmol/L HOEt N1,1,1NTf2,分离电压为15 k V、检测波长210 nm、高差10 cm、进样10 s的条件下,西酞普兰对映体在16 min内获得了基线分离,分离度为1.70。实验结果表明,CM-β-CD和离子液体HOEt N1,1,1NTf2联用能够提高西酞普兰对映体的分离度。     

光学活性的2-苄基-3-羟基丙酸合成

以丙二酸二乙酯为起始原料,经过苄基化、还原、乙酰化保护、氧化、水解等5个步骤,合成了标题化合物.以水为溶剂,对标题化合物与手性1-苯乙胺形成的非对映异构体盐进行手性拆分,得到了(R)-2-苄基-3-羟基丙酸和(S)-2-苄基-3-羟基丙酸.     

Molecular Modeling Study of Chiral Separation and Recognition Mechanism of β-Adrenergic Antagonists by Capillary Electrophoresis

Chiral separations of five β-adrenergic antagonists (propranolol, esmolol, atenolol, metoprolol, and bisoprolol) were studied by capillary electrophoresis using six cyclodextrins (CDs) as the chiral selectors. Carboxymethylated-β-cyclodextrin (CM-β-CD) exhibited a higher enantioselectivity power compared to the other tested CDs. The influences of the concentration of CM-β-CD, buffer pH, buffer concentration, temperature, and applied voltage were investigated. The good chiral separation of five β-adrenergic antagonists was achieved using 50 mM Tris buffer at pH 4.0 containing 8 mM CM-β-CD with an applied voltage of 24 kV at 20 °C. In order to understand possible chiral recognition mechanisms of these racemates with CM-β-CD, host-guest binding procedures of CM-β-CD and these racemates were studied using the molecular docking software Autodock. The binding free energy was calculated using the Autodock semi-empirical binding free energy function. The results showed that the phenyl or naphthyl ring inserted in the hydrophobic cavity of CM-β-CD and the side chain was found to point out of the cyclodextrin rim. Hydrogen bonding between CM-β-CD and these racemates played an important role in the process of enantionseparation and a model of the hydrogen bonding interaction positions was constructed. The difference in hydrogen bonding formed with the -OH next to the chiral center of the analytes may help to increase chiral discrimination and gave rise to a bigger separation factor. In addition, the longer side chain in the hydrophobic phenyl ring of the enantiomer was not beneficial for enantioseparation and the chiral selectivity factor was found to correspond to the difference in binding free energy.     

双相（O/W）识别手性萃取分离多巴对映体研究

为了研究多巴在D（L）-2酒石酸异丁酯1,2二氯乙烷有机相和羟丙基-β-环糊精水相萃取体系中的分配行为;运用双相（O/W）识别手性萃取,考察酒石酸构型和浓度、羟丙基-β-环糊精浓度、水相pH值等因素对萃取性能的影响。羟丙基-β-环糊精对S-多巴对映体的识别能力大于对R-多巴对映体的识别能力,而L-酒石酸异丁酯的识别能力刚好相反;在羟丙基-β-环糊精和L-酒石酸异丁酯萃取体系中,多巴外消旋体一次萃取分离后R和S对映体的分配系数（kR和kS）分别为8.92和5.34,分离因子α达1.67;同时pH值和萃取剂浓度对手性分离能力有显著的影响。双相（O/W）识别手性萃取具有较强的手性分离能力,它对外消旋体化合物的制备性分离有着十分重要的意义。     

手性流动相添加剂法拆分盐酸安非他酮对映体

以羧甲基-β-环糊精(carboxymethyl -β - cyclodextrin,简称CM -β - CD)为手性流动相添加剂,建立了盐酸安非他酮对映体拆分的高效液相色谱方法.系统考察了手性添加剂的种类及浓度、有机改性剂的比例、pH值和流速等因素对拆分的影响.结果表明:乙腈:甲醇:水-40:30∶30(体积比),p...     

Enantioselective separation of R,S-phenylsuccinic acid by biphasic recognition chiral extraction

A new process has been developed to separate phenylsuccinic acid (H₂A) enantiomers, based on the oppositely preferential recognition of hydrophobic and hydrophilic chiral selectors in organic and aqueous phases, respectively, which is named as biphasic recognition chiral extraction (BRCE). BRCE system is established by adding hydrophobic l-iso-butyl tartrate in organic phase and hydrophilic β-cyclodextrin (β-CD) derivative in aqueous phase, which preferentially recognize S-H₂A and R-H₂A, respectively. The studies performed involve two enantioselective extractions in a biphasic system, where H₂A enantiomers form four complexes with β-CD derivative in aqueous phase and l-iso-butyl tartrate in organic phase, respectively. Here it is shown that the efficiency of the extraction depends, often strongly, on a number of process variables, including the types of organic solvents and β-CD derivatives, iso-butyl tartrate configurations, the concentrations of the extractants and H₂A enantiomers, pH and temperature. Phase-equilibria in BRCE systems is governed by the complex chemical equilibria in both the organic and aqueous phases. By changing the monophasic recognition chiral extraction (MRCE) system into BRCE system, the enantioselectivity increases from 1.501 to 2.862. The maximum enantioselectivity for H₂A enantiomers is obtained at pH≤2.5 and the ratio of 2:1 of [l-(+)-iso-butyl tartrate] to [HP-β-CD]. The experimental results show that BRCE is of much stronger chiral separation ability than MRCE, which is due to utilization of the separation abilities of both tartrate and β-CD derivative. It may be very helpful to optimize the extraction systems and realize the large-scale production of pure enantiomers.     

手性流动相添加剂法拆分盐酸依替福林对映体

建立了以羧甲基-β-环糊精(CM-β-CD)作为手性流动相添加剂,高效液相色谱拆分标题化合物的方法。系统考察了流动相中添加剂的种类及浓度、有机修饰剂、pH、三乙胺的含量和流速等因素对拆分的影响。色谱分离条件:流动相(V(甲醇)∶V(乙腈)∶V(水)=15∶70∶15),CM-β-CD浓度为0.6 g/L,三乙胺含量为0.14%(V/V),pH为3.92,流速为0.2mL/min,检测波长214 nm,药物对映体得到良好分离。     

苯氧羧酸类除草剂的手性毛细管电泳

以7-CD为毛细管电泳手性选择剂,对苯氧羧酸类除草剂对映体的分离进行了研究。考察了手性选择剂的种类、7-CD浓度、SDS浓度、背景电解质浓度、pH值等对分离的影响。结果发现,选择30mmol·L11rCD＋100mmol·L11SDS＋75mmol·L-1H3P04作为电泳缓冲体系（pH值2．O）,2,4-滴丙酸、2,4,5-滴丙酸、2-（3-氯苯氧基）丙酸对映体完全分离,2-（4-氯苯氧基）丙酸、2-苯氧基丙酸对映体部分分离,分离度分别为3．42、8．27、2．83、0．89、0．50。     

水溶性β-环糊精反应萃取分离苯基琥珀酸对映体的平衡研究

This paper deals with the enantioseparation of phenylsuccinic acid (H2A) enantiomers by liquid-liquid reactive extraction using β-CD derivatives as aqueous selectors. Cyclodextrin and its derivatives can interact with guest molecules selectively to form complexes with different stabilities. Cyclodextrin derivatives are not soluble in organic liquids, but highly soluble in water. In this work, hydroxypropyl-β-cyclodextrin (HP-β-CD), hydroxyethyl- β-cyclodextrin (HE-β-CD) and methyl-β-cyclodextrin (Me-β-CD) were selected as chiral selectors in aqueous phase for the reactive extraction of phenylsuccinic acid enantiomers from organic phase to aqueous phase. The results show that the efficiency of the extraction depends, often strongly, on a number of process variables, including the types of organic solvents and β-CD derivatives, the concentrations of the extractants and H2A enantiomers, pH and temperature. HP-β-CD, HE-β-CD and Me-β-CD have stronger recognition abilities for R-phenylsuccinic acid than for S-phenylsuccinic acid. Among the three kinds of β-CD derivatives, HP-β-CD has the strongest separation ability. Excellent enantio-separation was achieved under the optimal conditions of pH of 2.5 and temperature of 5°C with a maximum enantioselectivity (a) of 2.38. Reactive extraction of enantiomers with hydrophilic β-CD derivatives is of strong chiral separation ability and can be hopeful for separations of various enantiomers at a large-scale.     

毛细管电泳法分离6种手性化合物

以羟丙基-β-环糊精作为手性选择剂,采用毛细管电泳法对氧氟沙星、特布他林、克伦特罗、美托洛尔、扁桃酸和苯基丁二酸等6种对映体进行手性分离条件研究。通过对羟丙基-β-环糊精的浓度、缓冲溶液pH值、电压和检测波长等影响手性分离主要因素的探讨,建立了能同时实现对6种对映体手性分离的方法;并采用对照品加入法将手性单体加入到对映体化合物中,确定了氧氟沙星对映体的出峰顺序。     

Selective Enantioseparation of Racemic Amlodipine by Biphasic Recognition Chiral Separation System

The biphasic recognition chiral extraction process was developed and applied to separate amlodipine enantiomer. The chiral extraction system contained tartaric acid derivatives in the organic phase and β-cyclodextrin derivatives in the aqueous phase. The effect of extraction equilibrium time and the influence of different types of tartaric acids, types of β-cyclodextrin derivatives, organic solvents, and buffer pH were investigated. The results indicated that hydroxypropyl-β-cyclodextrin (HP-β-CD) showed a higher recognition ability toward (S)-amlodipine than (R)-amlodipine while dibenzoyl-D-tartrate demonstrated the strongest ability among tartaric acid derivatives to bind with (R)-amlodipine. The distribution ratios for (S)-amlodipine (k_S) and (R)-amlodipine (k_R) gave optimum values at pH 5.0 of 16.54 and 0.78, respectively. Biphasic chiral recognition extraction has great significance for preparative separation of (S)-amlodipine. It can also be used to design and apply the enantioseparation process.     

基于β-环糊精/SiO_2手性固定相的薄层色谱法拆分DL-萘普生的研究

用β-环糊精(-βCD)键合硅胶合成了一种新型的β-环糊精/S iO2手性固定相,用红外对其进行了结构鉴定。将该手性固定相用于薄层色谱分离萘普生外消旋体,考察多种溶剂对萘普生外消旋体的展开效果,结果表明,乙酸乙酯∶氯仿(体积比)=1∶4为展开剂时,合成的手性固定相对DL-萘普生的分离度为1.45,具有很好的拆分DL-萘普生的能力。