Stereoselective interaction

The effect of the mobile phase modifier was investigated for a series of phen-oxypropionic acid (PEA) herbicides on a teicoplanin CSP [85, 86] an increasing enantioselectivity was found with increasing MeOH content in the mobile phase, attributed to restriction of the solute association with the TE CSP, which led to favorable stereoselective interactions. 

Chahfour, R.I., MacLaughlin, R.W., Lavoie, L., et al. (2003) Stereoselective interactions of peptide inhibitors with the P-amyloid peptide. J. Biol. Chem., 278, 34874-34881. 

F Kilar. Stereoselective interaction of drug enantiomers with human serum transferrin in capillary zone electrophoresis. Electrophoresis 17 1950-1953, 1996. 

When a CSP is applied, the separation mechanism is based on the differences in the interaction between the chiral selector in the stationary phase and the enantiomers of the solute. Depending on the nature of the selector and the type of the solute, the stereoselective interaction can be based on interactions of one or more different types such as inclusion complexation, Tr-jr-interaction, dipole stacking, hydrogen bonding, electrostatic interaction, hydrophobic interaction, and steric interaction [35]. In order to obtain chiral discrimination between the enantiomers, a three-point interaction is required between at least one of the enantiomers and the CSP [36]. The interactions can be of attractive as well as repulsive nature (e.g., steric and electrostatic interactions). 

Niopas I, Toon S, Rowland M. Further insight into the stereoselective interaction between warfarin and cimetidine in man. Br J Clin Pharmacol 1991 32 508-511. 

Casella L, Gullotti M, Poli S et al (1991) Spectroscopic and binding studies on the stereoselective interaction of tyrosine with horseradish peroxidase and lactoperoxidase. Biochem J... 

Yeung, D.T., Smith, J.R., Sweeney, R.E., Lenz, D.E., Cerasoli, D.M. (2008). A gas-chromatographic-mass spectrometric approach to examining stereoselective interaction of human plasma proteins with soman. J. Anal. Toxicol. 32 86-91. 

Doom, J.A., Thompson, C.M., Christner, R.B., Richardson, R.J. (2003). Stereoselective interaction of Torpedo californica acetylcholinesterase by isomalathion inhibitory reactions with (IR)- and (lR)-isomers proceed by different mechanisms. Chem. Res. Toxicol. 16 958-65. 

Figure 5.4 The structure of [ Ce(H20)4(al-P2Wi706i) 2] [16]- (Reprinted with permission from M.H. Dickman, et ah, Chiral polyoxotungstates. 1. Stereoselective interaction of amino acids with enantiomers of [Ce (al-P2Wi706i)(H20) c] - The structure of DL-[Ce2(H20)g(P2Wi706i)2], /no r an/c Chemistry, 40, no. 12, 2715-2719 (Figure 1), 2001. 2001 American Chemical Society.)...

M. E. Jones, B. C. Sallustio, Y. Purdie, and E J. Meffin, Enantioselective disposition of 2-arylpropionic acid non-steroidal anti-inflammatory drugs. II. 2-Phenylpropionic acid binding, /. Pharmacol. Exp Ther., 238 288 (1986). R. A. O Reilly, W. E Trager, C. H. Motley, and W. Howald, Stereoselective interaction of phenylbutazone with (12C/13C) warfarin pseudoracemates in man, /. Cfm. Invest., 65 746 (1980). 

Choonara lA, Cholerton S, Haynes BP, Breckenridge AM, Park BK. Stereoselective interaction between the R enantiomer of warfarin and cimetidine. Br J Clin Pharmacol 1986 21(3) 271-7. 

O Reilly RA, Goulart DA, Kunze KL, Neal J, Gibaldi M, Eddy AC, Trager WF. Mechanisms of the stereoselective interaction between miconazole and... 

Hieble JP, Hehr A, Li YO, Ruffolo RR, Jr. Molecular basis for the stereoselective interactions of catecholamines with a-adrenoceptors. Proc West Pharmacol Soc 1998 41 225-228. 

RA O Reilly, WF Trager, CH Motley, WN Howald. Stereoselective interaction of phenylbutazone with (12C/13 Qwarfarin pseudoracemates in man. J Clin Invest 65 746—753, 1980. 

Neutral and charged CD derivatives, with various functional groups, have been developed to induce different stereoselective interactions and enhance enantioselectivity and solubility. Their use in CE was first reported by Terabe for the separation of positional isomers [18]. Later, Fanah obtained a chiral separation in CZE by simply adding CD to the BGE [19]. 

From previous investigations it was postulate that muscarinic receptors possess four different subsites for antagonist binding, shown e.g. for the carbinols procyclidine and hexahy-dro-difenidol [43, 44]. Therefore, another aim of this study was to compare the antimuscarinic properties of the enantiomers of the hydroxymethyl-derivatives described above (3, 4, 8, 9) with their related diphenyl- (3a, 4a, 8a, 9a) as well as their dicyclohexyl analogues (3b, 4b, 8b, 9b) in order to interpret their stereoselective interaction witii the dififerent muscarinic receptor subtypes. 

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