镇痛药地佐辛的毛细管电泳手性分离研究

地佐辛作为阿片类镇痛药常用于术后止痛、癌症痛等。目前临床上地佐辛以外消旋体的形式给药。本文以麦芽糊精为手性选择剂,手性离子液体四甲基胺-L-酒石酸盐为添加剂,构建了毛细管电泳手性协同分离体系,并将该体系成功的应用于地佐辛对映体的手性分离。     

N,N-二丁基丙烯酰胺及其共聚物的合成

将丙烯酰氯与二丁基胺反应合成了N,N-二丁基丙烯酰胺(DBA),分别用红外光谱、碳谱分析了DBA的结构;DBA与丙烯酰胺(AM)经自由基微乳液聚合制备了水溶性疏水缔合共聚物P(AM-DBA),考察了共聚物中疏水单体含量、共聚物浓度、溶液温度对共聚物水溶液粘度的影响。结果表明,在试验范围内,P(AM-DBA)比聚丙烯酰胺具有更优异的耐温耐盐性能和明显的盐增稠现象。并解决了疏水缔合聚合物的水溶性与耐温耐盐性之间的矛盾。     

GPC测定环氧端基聚芳醚腈(E-PCE)的分子量

联用窄分布环氧端基聚芳醚腈试样的和ＧＰＣ谱图数据,确定了环氧端基聚芳醚腈在四氢呋喃溶剂中,３０℃下的Ｍａｒｋ－Ｈｏｕｗｉｎｋ常数为Ｋ＝５．５２＊１０＾－６,ａ＝１．３２２６,就分子量对性能的影响进行了讨论。     

3,3’,5,5’-四甲基联苯-4,4’-二羟乙基醚的合成与表征

以3,3’,5,5’-四甲基联苯二酚(TMBP)和2-氯乙醇为原料两步法合成了3,3’,5,5’-四甲基联苯-4,4’-二羟乙基醚。探讨了反应物物质的量比、碱用量、催化剂及反应温度对转化率的影响。结果表明,在n(TMBP)∶n(NaOH)∶n(2-氯乙醇)=1∶3.0∶2.5,反应时间为10h,反应温度为110℃条件下,总转化率达95.9%,纯度达99.1%。并用红外、质谱以及核磁等方法对产物结构进行了表征。     

4，4＇-二（2，6-二甲基苯氧基）二苯砜、三苯二醚和对苯二甲酰氯三元无规共聚物的合成与表征

在无水三氯化铝（A1C13）和N，N-二甲基甲酰胺（DMF）存在下，以1，4-二苯氧基苯（DPB）、4，4’-二（2，6-二甲基苯氧基）二苯砜（o-M2DPODPS）和对苯二甲酰氯（TPC）为单体，于1，2-二氯乙烷（DCE）中进行低温溶液缩聚反应，合成了一系列共聚物。用IR，DSC，WAXD，TGA等方法对共聚物进行表征和性能测试。研究结果表明，随着o-M2DPODPS含量的增加，共聚物的玻璃化转变温度（Tg）大幅提高，熔融温度（Tm）和结晶度则逐渐减小，溶解性能得到了一定的改善。     

磺化联苯侧基双二氮杂萘酮聚芳醚酮膜的制备

以1′,4-二(1,1′-联苯基)-6,6′-双二氮杂萘-1,4′-二酮、4-(4-羟苯基)-2,3-二氮杂萘-1-酮和4,4′-二氟二苯酮进行共聚合,经磺化改性制备了新型磺化联苯侧基双二氮杂萘酮聚醚酮(SPDPEKs).通过核磁共振波谱、红外光谱对SPDPEKs的结构进行表征.采用溶液浇铸法制备了SPDPEKs质子交换膜,对其离子交换容量(IEC)、溶胀率、质子传导率以及耐氧化性进行了测试.结果表明：SPDPEK质子交换膜的IEC介于0.75～1.77 mmol/g之间,在80℃下的吸水率介于9.2%～30.2%之间,溶胀率低于10%;SPDPEKs膜在95℃的质子传导率介于53.3～146.2 mS/cm,在80℃芬顿试剂中的破裂时间在3.4～5.3 h之间,溶解时间则介于12～36 h.SPDPEKs膜表现出良好的尺寸稳定性、质子传导性和耐氧化稳定性.     

CVD聚合制备聚(羟甲基对亚苯基二亚甲基)及其性能的研究

用化学气相沉积(CVD)聚合法制备了聚(羟甲基对亚苯基二亚甲基)(PPX-HM)膜,采用FTIR和元素分析的方法证实了其化学结构.对膜溶解性和抗化学氧化性能的研究表明PPX-HM膜具有优异的耐溶剂性和抗化学氧化性能.对PPX-HM膜热性能的研究表明羟甲基的引入使得膜的玻璃化转变温度降低,室温柔性增强,动态力学阻尼性能增大,热降解起始温度比聚对亚苯基二亚甲基(PPX)低,但主链降解温度比PPX反而高出约50℃.此外,羟甲基的引入使得膜的亲水性能大幅度提高,水汽透过性能也有所提高.     

1,1-二(对-二乙氨基苯基)-4-(α-萘基)-4-苯基-1,3-丁二烯的合成及其光电性能研究

以α-溴代萘和苯乙酮为主要原料合成了1-(α-萘基)-1-苯基-3-氯丙烯,该化合物与4,4'-双(二乙氨基)二苯甲酮经Grignard反应,脱水后得到目标产物1,1-二(对-二乙氨基苯基)-4-(α-萘基)-4-苯基-1,3-丁二烯(CT),产品纯度98.86%,收率36.4%.通过质谱与核磁共振对产物的结构进行了表征,并对其进行X-射线单晶衍射分析,确定了分子构型.以Y-TiOPc为电荷产生材料,CT为空穴传输材料制备的功能分离型光导体光导性能参数为:V0=-850V,VR=-20V,Rd=17.5V,E1/2=0.60lx·s,表明CT具有优良的空穴传输特性.     

手性有机多孔材料的合成及其手性拆分膜研究进展

随着光学纯化合物需求的不断增加,手性分离的研究在医药、化学、生物学等领域具有重要意义.膜分离法是近年来发展的一种新型节能技术,具有连续操作、易于放大、无污染等优点,被认为是一种具有潜力的大规模拆分对映异构体的方法.大多数一维聚合物手性分离膜的选择性与通量之间呈反向关系,且耐溶剂性差,导致分离性能不稳定,通量较低.有机多...     

无载体手性固定相拆分对映体

本文介绍了无载体纤维素三—(4—甲基苯甲酸酯)手性固定相对外消旋药物酮洛芬的拆分且就不同的柱尺寸及装填方式作了比较。为了反映无载体手性固定相的拆分能力,还将无载体柱与有载体柱、自制柱与日本柱作了比较。结果表明:无载体手性固定相对外消旋药物是有拆分能力的,只是其能力低于有载体的。若无载体手性固定相能与高新分离技术(如模拟移动床)相结合,将有望实现外消旋药物的低成本拆分。     

Simultaneous concentration and separation of enantiomers with chiral temperature gradient focusing

A new technique is demonstrated for the simultaneous concentration and high-resolution separation of chiral compounds. With temperature gradient focusing, a combination of a temperature gradient, an applied electric field, and a buffer with a temperature-dependent ionic strength is used to cause analytes to move to equilibrium, zero-velocity points along a microchannel or capillary. Different analytes are thus separated spatially and concentrated in a manner that resembles isoelectric focusing but that is applicable to a greater variety of analytes including small chiral drug molecules. Chiral separations are accomplished by the addition of a chiral selector, which causes the different enantiomers of an analyte to focus at different positions along a microchannel or capillary. This new technique is demonstrated to provide high performance in a number of areas desirable for chiral separations including rapid separation optimization and method development, facile reversal of peak order (desirable for analysis of trace enantiomeric impurities), and high resolving power (comparable to capillary electrophoresis) in combination with greater than 1000-fold concentration enhancement enabling improved detection limits. In addition, chiral temperature gradient focusing allows for real-time monitoring of the interaction of chiral analyte molecules with chiral selectors that could potentially be applied to the study of other molecular interactions. Finally, unlike CE, which requires long channels or capillaries for high-resolution separations, separations of equivalent resolution can be performed with TGF in very short microchannels (mm); thus, TGF is inherently much more suited to miniaturization and integration into lab-on-a-chip-devices.     

Capillary electrophoresis with electrochemical detection for chiral separation of optical isomers

The enantiomers of two amine derivatives were directly separated by capillary electrophoresis (CE), employing β-cyclodxtrin (β-CD) as a chiral additive in strongly alkaline solutions. The analytes were detected by electrochemistry, using a copper disk electrode at +675 mV vs Ag/AgCl reference electrode. Both the free enantiomers and the enantiomer-cyclodxtrin inclusion complexes could be detected using this approach, although the complexed forms gave lower oxidation currents than the free forms. Factors affecting the chiral CE separation of the analytes, such as working potential, concentration of running buffer and β-CD, and applied voltage, were extensively investigated. Under the optimum conditions, baseline separation of the enantiomers could be accomplished in less than 18 min. In addition, a successful application of the method to the enantiomeric purity determination confirmed its validity and practicability.     

Simultaneous separation of coplanar and chiral polychlorinated biphenyls by off-line pyrenyl-silica liquid chromatography and gas chromatography. Enantiomeric ratios of chiral congeners

A method for the unambiguous determination of 41 key polychlorinated biphenyls (PCBs) (including coplanar and chiral congeners) and the enantiomeric ratio of chiral congeners is described. The method includes a fractionation step using a 2-(1-pyrenyl) ethyldimethylsilylated silica column for separating the polychlorinated biphenyls according to the number of chlorine atoms in the ortho positions. High-resolution gas chromatography with an electron capture detector and an achiral column was used to determine the PCB congener content in each fraction. The enantiomeric ratio of chiral congeners was calculated by high-resolution gas chromatography with a mass spectrometry detector using a chiral column. The method was found to be inexpensive, rapid, effective, and reliable under the operational conditions proposed. It eliminates the main coelution problems among the polychlorinated biphenyl congeners. It also makes it possible to determine the enantiomeric ratio of nine chiral congeners using monodimensional gas chromatography. The method was applied successfully to the analysis of the coplanar and atropisomeric polychlorinated biphenyl congeners in dolphin liver samples. The enantiomeric ratio of nine chiral congeners is also reported for the first time.     

Evaluating chiral separation interactions by use of diastereomeric polymeric dipeptide surfactants.

Poly sodium N-undecyl leucine-leucine (poly SULL) is used as a diagnostic tool to investigate chiral molecular interactions via electrokinetic chromatography (EKC). Poly SULL has two chiral centers which are defined by two asymmetric carbons. Each chiral center of poly SULL can have two possible configurations (D or L). Consequently, four different optical configurations are possible within the surfactant molecule (L-L, D-D, L-D, and D-L). In this study, five chiral analytes of various charge states and hydrophobicities were used to investigate the role of electrostatic interactions and hydrophobicity on chiral recognition with polymeric dipeptide surfactants. These studies lead to a proposed hypothesis for interaction of the analytes with dipeptide surfactants. The hypothesis was tested and the contribution of the double chiral centers to this interaction was evaluated by use of two dipeptide surfactants in which one chiral amino acid is replaced by an achiral amino acid glycine, i.e., poly sodium N-undecyl L-leucine-glycine (poly L-SULG) and poly sodium N-undecyl L-glycine-leucine (poly L-SUGL). The results reported here provide new insights into the mechanism for chiral recognition of select chiral analytes by use of polymeric chiral surfactants.     

手性阳离子交换膜应用于多级电渗析分离DL-苯甘氨酸

将分离系数为1.05左右的手性阳离子交换膜用于四级电渗析过程分离DL-苯甘氨酸,当电流密度为46 mA/cm2,进料速度为0.2 mL/min时,过程的总体分离系数达到1.20左右,讨论了进料速度、电流密度对分离效果的影响,当进料速度增加或电流密度减小时都不利于分离.     

Enantiomeric separation and quantitative determination of atenolol in tablets by chiral high-performance liquid chromatography

The separation and quantitative determination of atenolol isomers by chiral high-performance liquid chromatography (HPLC) are described. Atenolol isomers were separated using a Chiralcel OD® column (250 × 4.6 mm,10 μm); the mobile phase was hexane-ethanol-diethylamine (75:25:0.1 v/v/v); ultraviolet detection was at 276 nm; and flow rate was 0.7 ml/min. The coefficient of variation and average recovery of (R)-isomer were 0.60% and 100.37%, respectively, for sample A and 0.69% and 100.63%, respectively, for sample B. The coefficient of variation and average recovery of (S)-isomer were 0.59% and 100.33%, respectively, for sample A and 0.63% and 99.78%, respectively, for sample B.     

Enantiomer separation by countercurrent chromatography using cinchona alkaloid derivatives as chiral selectors

Cinchona-derived anion-exchange-type chiral selectors have been adapted and employed in countercurrent chromatography (CCC) for the separation of enantiomers of N-derivatized amino acids and 2-aryloxypropionic acids. The accurate optimization of the enantioseparation in terms of solvent system composition, pH values, ionic strength, and CCC operating conditions was performed. A wide range of solvent mixtures was evaluated. Successful resolutions were achieved in systems such as ammonium acetate buffer/tert-amyl alcohol/methanol/heptane and especially ammonium acetate buffer/methyl isobutyl ketone or diisopropyl ether. Up to 300 mg (0.92 mmol) of N-(3,5-dinitrobenzoyl)-(+/-)-leucine was totally resolved in a single run using a 10 mM concentration of chiral selector in 122 mL of stationary phase. This amount could be increased up to 900 mg (2.77 mmol) when pH-zone-refining mode was applied. The results here presented account for the high potential of CCC as a preparative enantiomer separation technique.