手性药物的厚体液膜拆分及其动力学研究

【作者】 胡卫国；

【导师】 黄可龙；

【作者基本信息】 中南大学 ， 有机化学， 2007， 硕士

【摘要】 本文详细综述了现有的手性拆分技术，对手性药物的厚体液膜拆分进行了深入研究。以羟丙基-β-环糊精为手性选择剂，采用毛细管区带电泳拆分克伦特罗外消旋体。研究β-环糊精种类、浓度、缓冲液pH值及浓度、分离电压和操作温度等对分离的影响，并对分离条件进行优化：30 mmol／L羟丙基-β-环糊精，50mmol／L的磷酸盐缓冲液（pH 2.5），分离电压24kV，操作温度20℃，分离度可达到6.78。对手性拆分机理进行探讨，测定羟丙基-β-环糊精与两对映单体的结合常数及热力学参数，对毛细管区带电泳定量性能也进行考察。以D-二苯甲酰酒石酸（D-DBTA）和D-对甲基二苯甲酰酒石酸（D-DTTA）的组合作为手性选择剂，研究克伦特罗（Cle）对映体在水相和有机相中的萃取分配行为，建立了实验中优化的手性萃取条件：摩尔浓度比为1：1的D-DBTA和D-DTTA为组合手性选择剂，正辛醇为有机溶剂，水相pH值控制在7左右，对映体初始浓度为5.0 mmol／L，有机相中的对映体过量值（e．e．）可大于10％。以D-（+）-二苯甲酰酒石酸为手性载体，研究了克伦特罗对映体的厚体液膜法拆分，考察D-（+）-二苯甲酰酒石酸浓度、缓冲液pH值对手性拆分的影响。建立实验中优化的手性拆分条件和动力学拆分模型。在水相pH为7和手性载体与对映体浓度比为1：4的条件下，克伦特罗外消旋体能被有效拆分，分离因子大于1.08。同时进行动力学分析，测定出膜-料液界面的萃取反应表观速率常数k₁和膜-反萃相界面的反萃取表观速率常数k₂。结果表明，PPL单体的跨膜迁移过程可以用两个串联的准一级不可逆过程进行描述。更多还原

【Abstract】 Chiral technologies were reviewed in detail in this paper, and the resolution ofclenbuterol（Cle） by bulk liquid membrane （BLM） were further investigated. Amethod for capillary electrophoretic enantiomeric resolution of racemic clenbuterolhas been established with HP-β-CD as the chiral selector. General equations anddata analysis approach are presented to relate molibilities to equalibrium constantsin simple binding equilibria and used to determine binding constants andthermodynamic parameters for host-guest complexation of clenbuterol enantiomerswith HP-β-CD. The effects of type and concentration ofβ-CDs, buffer type and itsconcentration, pH of buffer, separation voltage and capillary temperature wereinvestigated in detail, respectively. The appropriate conditions was: 30 mmol/LHP-β-CD, 50 mmol/L phosphate solution （pH 2.5） as running buffer, separationvoltage in 24 kV, and operation temperature Of 20℃, the baselines separation couldbe obtained with resolution of 6.78. The quantitative ability of capillary zoneelectrophoresis also be researched.The distribution behavior of clenbuterol enantiomers was examined in theaqueous and organic phase containing combinatorial chiral selectors:Dibenzoyl-D-tartaric acid （D-（+）-DBTA） and Di-p-toluoyl-D-tartaric acid （D-（+）-DTTA）, in order to establish the optima chiral extraction conditions in thisexperiment. The influences of the molar concentration ratios of combinatorial chiralselectors, organic solvents, lipophilic anions and pH in aqueous phase, temperatureon chiral extraction performance were investigated, and the thermodynamic.parameters for chiral extraction procedure were also determined. It is shown that theenantiomer excess （e.e.％） can be above 10% under the optima chiral extractionconditions.Bulk liquid membrane containing chiral carrier was used for resolution ofracemic clenbuterol, the optimal chiral separation conditions and the kineticresolution model were established in this experiment. The influences of the molarconcentration ratio of chiral carrier and pH in aqueous phase on performances ofchiral resolution were investigated. The chiral resolution of bulk liquid membranewas analysed by means of a kinetic model involving two consecutive irreversiblefirst order reactions. The pseudo-first order apparent rate constants, k₁ or k₂ ofinterfacial reactions in membrane-feed solution interface or membrane-strippingsolution interface were determined. The results show that the separation factor is above 1.08 under the conditions of pH 7 in aqueous phase with the molarconcentration ratio of 1: 4, and the kinetic resolution of clenbuterol can beevaluated by two consecutive irreversible first order reactions under the optimalconditions.更多还原