手性固定相法拆分卟唑羧酸衍生物对映异构体

用直链淀粉－三（3，5－二甲基苯基氨基甲酸酯）手性固定相，在正相条件下首次拆分了6种卟唑羧酸衍生物对映异构体。考察了流动相中不同的酸性添加剂、不同的正丙醇浓度对样品和拆分的影响。     

手性高效液相色谱法测定SR-生物丙烯菊酯对映体的光学纯度

 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(CSP)。用该固定相优化了生物丙烯菊酯对映体的分离条件 ,利用色谱峰面积测定了 3种SR 生物丙烯菊酯对映体的光学纯度。结果表明 ,在CDMPC CSP上用高效液相色谱法 (HPLC)测定SR 生物丙烯菊酯对映体的光学纯度、评价样品的质量优劣是一种非常理想的方法。     

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。     

顺式、反式氯氰菊酯和烯唑醇对映异构体的手性拆分

将纤维素-三(3,5-二甲基苯基氨基甲酸酯)(CDMPC)涂敷于氨丙基硅胶上制备成高效液相色谱(HPLC)手性固定相,对手性农药顺式、反式氯氰菊酯和烯唑醇对映异构体在正相条件下进行了手性拆分。分别以正己烷和石油醚为流动相,考察改性剂的含量;在正己烷流动相条件下考察了色谱柱长度、温度对拆分效果的影响。试验结果显示,改性剂含量的减少、长色谱柱及降低温度均有利于对映体的分离。该手性固定相对顺式、反式氯氰菊酯具有非常强的立体选择性,对烯唑醇也有较好的拆分能力。     

测定手性有机酸对映体纯度的新试剂

用NMR技术测定微量手性化合物的对映体纯度,已有多种方法。其中,加手性镧化物位移试剂法适用面最广,但对有机酸,结果常不理想。另一种使用较广的方法是加手性试剂,将样品中两对映体转变成非对映异构体,然后比较非对映基因NMR信号的强度,确定原样品中对映体的组成比例。国外已出售的手性试     

手性固定相法拆分咔唑羧酸衍生物对映异构体

用直链淀粉－三（３,５－二甲基苯基氨基甲酸酯）手性固定相,在正相条件下首次拆分了６种咔唑羧酸衍生物对映异构体。考察了流动相中不同的酸性添加剂、不同的王丙醇浓度对样品保留和拆分的影响。     

Chiralcel OD-RH手性柱拆分卡维地洛对映体

采用Ch iralcelOD-RH(纤维素3,5-二甲基苯基氨基甲酸酯)手性固定相高效液相色谱法研究了乙腈-高氯酸钠缓冲盐体系对卡维地洛的手性拆分情况,讨论了流动相的各个因素(有机相的种类和比例、缓冲盐浓度、酸度等)对手性拆分的影响。在乙腈-高氯酸钠缓冲盐(pH 5.5,50 mmol/L)的体积比为35∶65的色谱条件下,卡维地洛对映体获得了基线分离。     

脲衍生物型手性固定相拆分氟西汀对映体

利用脲衍生物型手性色谱柱拆分药物氟西汀，主要优化了正相分离条件，并讨论了异构体的出峰次序；认为固定相中两个手性中心分别与异构体发生氢键及π－π电子授－受作用，且这两种作用力的强度对不同构型的异构体是不同的，流动相组成主要影响异构体的分析时间。     

手性试剂TMPEA用于手性酮对映体纯度测定的研究

β-三氟甲基-β甲氧基β-苯基乙胺（TMPEA）是含氨基功能团的手性试剂[1]．由于胺可将按酸转变成酸胺，该试剂已成功地用于手性有机酸对映体的纯度测定[2]．考虑到胺同样可将醛酮转变成亚胺，本文进一步探讨了TMPEA用于手性醒酮对映体纯度测定的可行性．用R－（－）－TMPEA及dl－TMPAE分别与下列4种手性酮反应，制备相应的非对映异构亚胶：比较光活亚胺及相应的非对映异构体混合物亚腔的NMR谱，可确定各组非对映异构亚胺‘HNMR位移差（以OCH为探针基团）和’‘FNMR的位移差（以CF为探针基团）（表1）．TablelCheffiicalshif…     

Determination of Repertaxin Enantiomeric Purity by HPLC on Chiral Stationary Phase

A precise and sensitive LC method for the determination of repertaxin enantiomeric purity has been developed and validated. Baseline separation with a resolution higher than 2.0 was accomplished within 20 min using a Chiralpak AD-H column (250 × 4.6 mm; particle size 5 μm) and n-hexane:2-propanol (90:10 v/v) as mobile phase at a flow rate of 1 mL min⁻¹. Eluted analytes were monitored by UV detection at 260 nm. The effects of mobile phase composition, temperature and flow rate on enantiomeric selectivity and on resolution of enantiomers were investigated. Calibration curves were plotted within the concentration range between 0.002 and 1.0 mg mL⁻¹ (n = 3), and relative standard deviation (RSD) of the inter-batch assay and intra-batch assay was less than 1.27 and 1.16 %. LOD and LOQ for repertaxin were 0.65 and 2.19 μg mL⁻¹; those for its enantiomer were 0.70 and 2.34 μg mL⁻¹, respectively. The method was evaluated and validated by analysis of bulk samples of repertaxin of different enantiomeric purity. It was demonstrated that the method was accurate, robust, and sensitive, and enabled practical analysis of real samples.

     

纤维素三苯甲酸酯作为薄层色谱固定相拆分手性化合物

用超声的方法合成了纤维素三苯甲酸酯(CTB),并将得到的产物用红外光谱与元素分析进行了表征。将该种手性固定相(CSP)用于薄层色谱分离手性化合物,分别采用TEAA,乙腈∶TEAA=2∶1及乙酸乙酯∶水∶冰乙酸=6∶2∶1作为展开剂,使2-(9-蒽基)-2-甲氧基乙酸、2-(9-蒽基)-2-羟基乙酸及苯丙氨酸都获得了完全分离。     

Investigation of Enantiomer Separation by LC with a New Bonded Cellulose 3,5-Dimethylphenylcarbamate Chiral Stationary Phase

A chiral stationary phase has been prepared from the 3,5-dimethylphenylcarbamate of cellulose chemically bonded to 3-aminopropylsilica gel at the 6-positions of the glucose units. The phase has been used to study direct liquid chromatographic enantioselective separation of five racemates. The effects on resolution of modifiers (alcohols, THF, and chloroform), flow rate, and temperature were investigated. It was found that the concentration and structure of the alcohol modifier can affect the separation; enantiomer separations were improved to different extents by addition of THF or chloroform to the mobile phase. Flow rate and temperature can also effect the resolution of racemates. In the range 10–40°C there was a linear relationship between ln k (or ln α) and 1/T (r > 0.98) for four of the compounds. These results indicate retention mechanism does not change as a function of temperature.     

脲衍生物型手性固定相拆分噻利洛尔对映体

用脲衍生物型手性固定相直接拆分了药物对映体噻利洛尔。优化的正相色谱流动相的组成为正己烷／１,２－二氯乙烷／乙醇（７７∶２１∶２,Ｖ／Ｖ／Ｖ）。实验表明,流动相中乙醇含量的改变对分离度产生了较大的影响;不同极性调节剂的使用表现出了不同的拆分效果。最后讨论了异构体的出峰次序,认为异构体与固定相的手性中心之一的氢键作用力是造成异构体分离的主要因素。     

Chiral Separation of Nateglinide and its L Enantiomer on a Molecularly Imprinted Polymer-Based Stationary Phase

A new chiral stationary phase for nateglinide (N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine) based on a molecularly imprinted polymer has been prepared by non-covalent imprinting. For chromatographic analysis the effects on the separation of mobile phase composition, flow rate, and temperature were investigated, and the optimum conditions for HPLC were shown to be: mobile phase, acetonitrile; flow rate, 0.5 mL min^?1; temperature, 25 °C. It was shown that the nateglinide-imprinted polymer was capable of recognizing the enantiomeric difference between nateglinide and its L enantiomer, whereas the non-imprinted polymer had no such ability. Scatchard analysis was used to investigate the binding characteristics of the nateglinide-imprinted stationary phase; this indicated that two classes of binding site were present in the imprinted polymer. The equilibrium dissociation constant (K _D) and the apparent maximum number (Q _max) of high- and low-affinity binding sites were 3.7 × 10^?4 mol L^?1 and 11.38 μmol g^?1, and 1.81 × 10^?3 mol L^?1 and 27.73 μmol g^?1, respectively.     

苯丙醇对映体在酰胺型手性固定相上的分离

对于手性对映体苯丙醇在3种Pirkk型手性固定相（CSP）Whelk-O 1、DNB-Leu和DNB-Pg上直接分离进行了研究。考察了流动相极性以及温度对分离的影响，发现在常用的范围内无法获得分离，仅有Whelk-O1在流动相极性的极端条件下（正己烷／异丙醇=99．5／0．5，V/V）能够被直接分离。在较低温度0℃和流速1mL／min的优化条件下能获得基线分离。用旋光检测器与液相色谱串联的方式确定了手性拆分结果，并确定了（-）苯丙醇优先洗脱的顺序。针对这种流动相极性极端条件下的分离，结合有关理论，进一步探讨了分离机理。     

苯丙醇对映体在酰胺型手性固定相上的分离

对于手性对映体苯丙醇在3种Pirkle型手性固定相(CSP)Whelk-O 1、DNB-Leu和DNB-Pg上直接分离进行了研究.考察了流动相极性以及温度对分离的影响,发现在常用的范围内无法获得分离,仅有Whelk-O1在流动相极性的极端条件下(正己烷/异丙醇=99.5/0.5,V/V)能够被直接分离.在较低温度0 ℃和流速1 mL/min的优化条件下能获得基线分离.用旋光检测器与液相色谱串联的方式确定了手性拆分结果,并确定了(-)苯丙醇优先洗脱的顺序.针对这种流动相极性极端条件下的分离,结合有关理论,进一步探讨了分离机理.