涂敷纤维素类手性固定相对甲霜灵中间体的高效液相色谱拆分

通过在自制的球形氨丙基硅胶上涂敷纤维素－三（3，5－二甲基苯基氨基甲酸酯）（CDMPC）制备了手性固定相，并采用该手性固定相成功地对甲霜灵中间体进行了高效液相色谱拆分；考察了由不同比例的正己烷和异丙醇组成的流动相对甲霜灵中间体分离效果的影响。     

纤维素-三（4-甲基苯甲酸酯）手性固定相拆分5种芳基丙酸类药物对映体及其制剂的含量测定

采用纤维素-三（4-甲基苯甲酸酯）（CTMB）手性固定相,利用反相色谱法研究了氟比洛芬、普拉洛芬、布洛芬、萘普生、洛索洛芬5种芳基丙酸类手性药物的色谱拆分行为。考察了流动相组成、酸碱添加剂及柱温对上述5种药物对映体分离的影响,并通过热力学研究及对映体结构分析对CTMB固定相的手性拆分机理进行了探讨。结果表明,除萘普生采用乙腈-0.1%（v/v）甲酸溶液外,以甲醇-0.1%（v/v）甲酸水溶液为流动相可使普拉洛芬、洛索洛芬、氟比洛芬和布洛芬的对映体间的分离度均大于1.5,CTMB固定相对这5种芳基丙酸类药物的手性拆分能力依次为普拉洛芬>洛索洛芬>氟比洛芬>布洛芬>萘普生。在各自的优化色谱条件下,将方法应用于上述5种药物制剂的含量测定,结果令人满意。     

以纤维素苯甲酸酯类为薄层色谱固定相对手性化合物的拆分

用超声方法合成了3种纤维素苯甲酸酯类手性固定相:三(苯甲酰基)纤维素(CTB),三(4-氯苯甲酰基)纤维素(CTPCB)和三(2-氯苯甲酰基)纤维素(CTOCB);用红外光谱和元素分析对其进行了结构鉴定.将该类手性固定相(CSP)用于薄层色谱分离手性化合物,分别采用TEAA,乙腈-TEAA(体积比2:1),乙酸乙酯-水-冰醋酸(体积比6:2:1),正丁醇-冰醋酸-水(体积比4:1:1)及乙酸乙酯-甲醇-30%(体积分数)醋酸(体积比5:3:2)作为展开剂,使2-(9-蒽基)-2-甲氧基乙酸、2-(9-蒽基)-2-羟基乙酸、苯丙氨酸、组氨酸及扑尔敏5种手性物质都获得了完全分离;在合成的3种手性固定相中,CTB的手性拆分能力较强,CTPCB和CTOCB的拆分能力稍差.     

禾草灵对映异构体在高效液相色谱手性固定相上的拆分

合成了手性纤维素-三(4-甲基苯甲酸酯)(CTMB)，并涂敷于氨丙基硅胶上，制备成手性固定相(CSP)；用高效液相色谱法在该手性固定相上对农药禾草灵外消旋体进行了拆分；考察了流动相组成、温度、醇效应对禾草灵对映体拆分及保留的影响，由实验结果对禾草灵对映体之间的-(ΔG^￠)π,s、（ΔH^￠）π,s、（ΔS^￠）π,s进行了计算，并对其在柱上保留机理进行了讨论。     

外消旋萘普生酯类在四种纤维素衍生物手性柱上分离及手性 识别机理研究

在纯聚合物型的纤维素三醋酸酯(CTA)、纤维素三苯甲酸酯(CTB)与涂敷型的CTB、纤维素三(4-甲基苯甲酸酯)(CTMB)四种纤维素衍生手性柱上成功地分离了几种外消旋萘普生酯,研究了流动相组成以及溶质的结构对手性分离的影响,探讨了纤维素衍生物手性固定相对外消旋萘普生酯手性识别的机理,得出溶质在固定相手性空腔中体积大小的适应性,尤其是立体结构上的空间适应性是手性识别的关键,不同的固定相这种适应性有所不同,     

外消旋萘普生酯类在四种纤维素衍生物手性柱上分离及手性 识别机理研究

在纯聚合物型的纤维素三醋酸酯(CTA)、纤维素三苯甲酸酯(CTB)与涂敷型的CTB、纤维素三(4-甲基苯甲酸酯)(CTMB)四种纤维素衍生手性柱上成功地分离了几种外消旋萘普生酯,研究了流动相组成以及溶质的结构对手性分离的影响,探讨了纤维素衍生物手性固定相对外消旋萘普生酯手性识别的机理,得出溶质在固定相手性空腔中体积大小的适应性,尤其是立体结构上的空间适应性是手性识别的关键,不同的固定相这种适应性有所不同,     

高效液相色谱手性固定相法分离取代环己酮及取代环己醇的对映体

在4种自制的涂敷型纤维素衍生物手性柱，即纤维素三苯甲酸酯(CTB)、纤维素三(4-甲基苯甲酸酯)(CTMB)、纤维素三苯基氨基甲酸酯(CTPC)和纤维素三(3，5-二甲基苯基氨基甲酸酯)(CDMPC)与小分子的Prikle型(S，S)-Whelk—O1手性柱上对取代环己酮及取代环己醇进行了对映体分离。研究了溶质的立体结构因素对手性分离的影响，并初步探讨、比较了溶质在这两种手性柱上的手性识别的机理。结果发现，在(S，S)-Whelk—O1柱上溶质与固定相之间的吸引作用是手性识别的主要原因，而对于纤维素衍生物手性柱，溶质的空间结构在手性空腔中的空间适应性可能是手性识别的关键。     

纤维素-三(4-甲基苯甲酸酯)手性固定相的制备及其在拆分叔丁基亚磺酰胺对映体中的应用

分别在自制的纤维素-三(3,5-二甲基苯基氨基甲酸酯)(CDMPC)和纤维素-三(4-甲基苯甲酸酯)(CTMB)涂覆型固定相上对叔丁基亚磺酰胺对映体进行手性拆分,并考察了流动相中异丙醇的含量对手性拆分的影响。结果表明,叔丁基亚磺酰胺在CTMB固定相上的分离效果更佳。随着异丙醇含量的减少,叔丁基亚磺酰胺对映体在两根色谱柱上的分离度和保留时间均随之增加。对CTMB固定相进一步探究柱温的影响,结果表明较低的温度有利于对映体保持稳定的手性构型,更易于与固定相反应。     

制备分离农药甲霜灵对映体的高效液相色谱法

用高效液相色谱法对自制的纤维素－三（3，5－二甲基苯基氨基甲酸酯）手性制备柱的手性拆分能力进行了评价，并且在此制备柱上完成了对手性农药甲霜灵进行了半制备分离；同时对手性农药甲霜灵在纤维素－三（苯基氨基甲酸酯）、直链淀粉－三（苯基氨基甲酸酯）、纤维素－三（4－甲基苯甲酸酯）手性分析柱上的手性拆分进行了研究。     

高效液相色谱中的纤维素衍生物手性固定相

评述了高效液相色谱中纤维素衍生物手性固定相直接拆分对映体的进展，介绍了纤维素衍生物的主要类型，纤维素衍生物作手性固定相三种不同方式的特点以及新的纤维素衍生物手性固定相应用，并结合色谱，NMR和分子模型设计和理论计算等方法讨论了纤维素衍生物手性固定的拆分机理。     

Synthesis of new chiral pyrylium salts and their phosphinine and pyridine derivatives

Despite their versatility, chiral pyryliums are almost unknown in the literature. Reported here is the synthesis of several new chiral pyrylium salts and the corresponding pyridines and phosphinines. This work more than doubles the number of reported chiral pyryliums, and also represents the first racemizable/epimerizable pyryliums. The derived phosphinines and pyridines represent rare α-chiral ligands for transition metals.     

Chiral Carbon Nanorings: Synthesis,Properties and Hierarchical Self-assembly of Chiral Ternary Complexes Featuring a Narcissistic Chiral Self-Recognition for Chiral Amines

We report the synthesis and chiroptical properties of novel chiral carbon nanorings S p-/Rp-[12]PCPP containing a planar chiral [2.2]PCP unit, and demonstrate that S p-/Rp-[12]PCPP can not only host crown ether 18-Crown-6 to form ring-in-ring complexes with a binding constant 3.35×10³ M⁻¹, but also accommodate the complexes of 18-Crown-6 and S/R-protonated amines to form homochiral S @Sp -/ R @Rp - and heterochiral S @Rp -/ R @Sp - ternary complexes, displaying significantly larger binding constants of up to 3.31×10⁵ M⁻¹ depending on the chiral guests. Importantly, homochiral S @Sp -/ R @Rp - ternary complexes exhibit an enhanced CD signal, while the heterochiral S @Rp -/ R @Sp - ones have a constant CD signal compared with the chiral carbon nanorings, respectively, which suggests that homochiral S @Sp -/ R @Rp - ternary complexes display a highly narcissistic chiral self-recognition for S/R-protonated chiral amines, respectively. Finally, the chiral ternary complexes can be further applied to determine the ee values of chiral guests. The findings highlight a new application of carbon nanorings in supramolecular sensors, beyond the common recognition of π-conjugated molecules.     

Synthesis and structural characterization of chiral dicationic imidazolophanes

Various chiral dicationic benzimidazolophanes were obtained from optically pure (S)-BINOL, benzimidazole and a suitable aryl alkyl dibromide.     

Designing chiral amido-oxazolines as new chelating ligands devoted to direct Cu-catalyzed oxidation of allylic CH bonds in cyclic olefins

A new type of amido-oxazoline ligands was conveniently synthesized from inexpensive and commercially available materials in high yields and enantiomeric excesses. The corresponding chiral copper complexes with this class of ligands [C₂ symmetric S,S-bis(amido-oxazoline-Cu(II) complex] were synthesized accordingly. The ORTEP diagram of ligand 6a and complex 6a-copper were compared and characterization of the complex confirmed the involvement of both dentate parts of the ligands, the oxygen and nitrogen atoms, in complexation with copper. The utilization of this amido-oxazoline ligands in the copper-catalyzed enantioselective esterification of allylic CH bonds of cyclic olefins with tert-butyl-4-nitrobenzoperoxoate resulted in the highest activities, yields (up to 95%) and enantioselectivities (up to 96%) in the presence of HZSM-5 zeolite. These new findings highlight the protocol as one of the most attractive and useful methods for the oxidation of the asymmetric allylic CH bond of cycloalkenes compared to other methodologies reported in the literature.     

烯烃的有机催化不对称环氧化反应

介绍了用手性酮，手性亚胺盐为催化剂以及手性胺为催化剂前体的新型有机催化不对称环氧化反应。     

Immobilization of cellulose phenylcarbamate onto silica gel via in termolecular polycondensation of triethoxysilyl groups introduced with (3-glycidoxypropyl)triethoxysilane

Cellulose 3,5-dimethylphenylcarbamate was successfully immobilized onto bare silica gel for HPLC through the intermolecular polycondensation of triethoxysilyl groups, which were introduced onto the cellulose derivative via epoxide ring-opening reaction under acidic conditions. The immobilized-type chiral packing material (CPM) exhibited high chiral recognition ability and could be used with various eluents, which are incompatible with the conventional CPMs prepared by coating the derivative onto silica gel.     

含磷手性化合物在多聚糖类手性固定相上的手性分离

在纤维素 三(3,5 二甲基苯基氨基甲酸酯)(ChiralcelOD)和直链淀粉 三(3,5 二甲基苯基氨基甲酸酯)(ChiralpakAD H)手性固定相上,采用高效液相色谱正相条件,分离了系列含磷手性化合物。考察了流动相中有机改性剂的种类及浓度对手性分离的影响;研究了化合物的结构与保留及对映体选择性的关系;并探讨了手性识别机理。     

Novel chiral solvating agents derived from natural amino acid: enantiodiscrimination for chiral α-arylalkylamines

Two benzo[de]isoquinoline 1,3-dione amino acids 1 and 2 were readily prepared, and their enantiodiscriminating ability were investigated by ¹H NMR spectroscopy. It was found that 1 exhibited an excellent chiral recognition ability toward chiral α-phenylethylamine and some of its derivatives, leading to clear baseline separation of the multiplet of the probe groups in two enantiomers. The stoichiometric ratio and association constants of some host-guest complexes were determined. The interactions between the hosts and guest 3 were further studied by intermolecular NOE experiment and ESI-MS.     

Past,present, and future developments in enantioselective analysis using capillary electromigration techniques

Enantioseparation of chiral products has become increasingly important in a large diversity of academic and industrial applications. The separation of chiral compounds is inherently challenging and thus requires a suitable analytical technique that can achieve high resolution and sensitivity. In this context, CE has shown remarkable results so far. Chiral CE offers an orthogonal enantioselectivity and is typically considered less costly than chromatographic techniques, since only minute amounts of chiral selectors are needed. Several CE approaches have been developed for chiral analysis, including chiral EKC and chiral CEC. Enantioseparations by EKC benefit from the wide variety of possible pseudostationary phases that can be employed. Chiral CEC, on the other hand, combines chromatographic separation principles with the bulk fluid movement of CE, benefitting from reduced band broadening as compared to pressure-driven systems. Although UV detection is conventionally used for these approaches, MS can also be considered. CE-MS represents a promising alternative due to the increased sensitivity and selectivity, enabling the chiral analysis of complex samples. The potential contamination of the MS ion source in EKC-MS can be overcome using partial-filling and counter-migration techniques. However, chiral analysis using monolithic and open-tubular CEC-MS awaits additional method validation and a dedicated commercial interface. Further efforts in chiral CE are expected toward the improvement of existing techniques, the development of novel pseudostationary phases, and establishing the use of chiral ionic liquids, molecular imprinted polymers, and metal-organic frameworks. These developments will certainly foster the adoption of CE(-MS) as a well-established technique in routine chiral analysis.