High Performance Liquid Chromatography Chiral Stationary Phase Separation Of Drug Enantiomers

This dissertation focuses on the enantioseparation using macrocyclic antibiotics chiral stationary phases (CSPs) by high performance liquid chromatography (HPLC), including enantioseparation of chiral compounds, study of several factors concerning chiral separation and discussion of chiral recognition mechanism.In Chapter 1, the importance and methods of chiral separation is briefly introduced.In Chapter 2, the literatures of three kinds of CSPs, macrocyclic CSPs, polysaccharide derivative CSPs and Pirkle type CSPs are briefly reviewed.In Chapter 3, Under polar organic mode, the seven amino alcohols Propranolol , Metoprolol, Bisoprolol fumarate, Atenolol, Salbutamol, Isoprenaline, Metoprolol, Labetalol were enationseparated on teicoplanin CSP, using methanol as mobile phase and HOAc and TEA as mobile phase additives. When the proportion of HOAc and TEA was 1:1, the retention factors and the resolutions of seven amino alcohols were decreased with the increase of HOAc/TEA concentration, separation factors kept constant. The excessive acid increased the polarity of mobile phase,the eluting ability was increased. Without HOAc additive, the retention factors of the amino alcohols were decreased with the increase of the amount of TEA, separation factors kept constant., except labetalol. The polarity of mobile phase increased with the increasing of TEA concentration, so the hydrogen bonding between solutes and CSPs decreased. All the results showed that the proportion of HOAc and TEA didn't change the essential of chiral separation.In Chapter 4, Under polar organic mode, the seven amino alcohols Propranolol , Metoprolol, Bisoprolol fumarate, Atenolol, Salbutamol, Isoprenaline, Metoprolol, Labetalol were enationseparated on teicoplanin CSP, phenylisocyanate teicoplanin (Phe-Te), and 3, 5-dimethylphenylisocyanate teicoplanin (DMP-Te) using methanol as mobile phase and HOAc and TEA as mobile phase additives.The mechanism of enantioseparetion was studied and the different behavior of chiral separation was compared.Different structure of CSP influenced the behavior of chiral separation.Seven amino alcohol have the similar trend on each CSP.Retention factors decreased with the increased of concentration of HOAc/TEA.AH in all, amino alcohol got the longest retention on DMP-TE CSP,while TE shortest.This is becauseπ-πand dipole-dipole of Te was less than Phe-Te and DMP-Te.It indicated thatπ-πand dipole-dipole benefit to retention.The enantioseparation of amino alcohol was best on Te.The hydrogen bonding was most on Te,so hydrogen bonding contributed to enantioseparation.HOAc and TEA can change the charge of the surface of solutes and CSPs,even the chiral cavity can influence the result of enantioseparation.Without HOAc,by fixed the concentration of TEA at 0.05, Propranolol, Bisoprolol fumarate,Metoprolol got better enantioseparation on DMP-Te than on Phe-Te.Maybe these solutes are more suitable for the cavity of DMP-Te.Strong retention didn't mean good chiral separation.The separation factor was nearly unchanged on each CSP,it indicated that the proportion of HOAc/TEA didn't influence the essential of chiral separation.In Chapter 5,the enantioseparation of a group of chiral compound with similar structure correspondingly was studied on three kinds of coated cellulose derivative chiral columns(CDMPC,CTB,CTMB),Pirkle type (S,S)-Whelk-Ol chiral column—Benzoin, Benzoin ethyl ether, Benzoin n-butyl ether.Three solutes all got enantioseparation on CDMPC.On four CSPs,the mechanism of enantioseparation of these three solutes was discussed:(1) Benzoin got the best chiral separation on CDMPC,and then Benzoin ethyl ether.The alcohol additives in the mobile phase influence the chiral recognition through the change of solid environment of the chiral cave on CDMPC.The hydrogen bond interaction also influence the enantioseparation.(2) Benzoin, Benzoin ethyl ether got enantioseparation on CTB,but Benzoin n-butyl ether didn't got chiral separation under any mobile phase.It indicated that Benzoin n-butyl ether didn't suitable for the cavity of CTB.The hydrogen bonding interaction is not important for the enantioseparation.Alcohol with small volumn is benefit for enantioseparation on CTB.(3) Only Benzoin got enantiosepation on CTMB, Benzoin n-butyl ether didn't got chiral separation under any mobile phase.lt indicated that Benzoin ethyl ether and Benzoin n-butyl ether didn't suitable for the cavity of CTMB. The hydrogen bonding interaction is not important for the enantioseparation.(4) Stereo factor is important for the enantioseparation on Pirkle type (S,S)-Whelk-Ol chiral column.In Chapter 6, four new CSPs, phenylisocyanate teicoplanin (Phe-TE), m-methylphenyl isocyanate vancomycin (MP-Van), 3, 5-dimethylphenylisocyanate teicoplanin (DMP-TE) and p-chlorophenyl isocyanate vancomycin (PCl-Van) are synthesized from the macrocyclic glycopeptide vancomycin CSP (Van),using derivative agents, phenylisocyanate, teicoplanin m-methylphenyl isocyanate, 3, 5-dimethylphenylisocyanate or p-chlorophenyl isocyanate.Evaluation and comparison of these five Van-based CSPs are processed with 3 recemates under PO (polar organic) mode.The polarity,hydrogen bonding and electrostatic interaction of derivative CSPs decreased whileπ-πand hydrophobic interaction increased. Fluoxetine got chiral separation on the five CSPs while Duloxetine and Paroxetine got chiral separation on MP-Van and DMP-Van.