Stereoselective binding

Fig. 4 Stereoselective binding study of verapamil to AGP and desialylated AGP using frontal analysis. Electropherograms of 50 /aM racemic verapamil solution (A), 50 /U.M verapamil solution in 50 jjM human al-acidic glycoprotein solution (B), and 50 /jM verapamil solution in 50 /jM asiaolo al-acidic glycoprotein solution (C). (Reprinted with permission from Ref. 54. Copyright 2001 Elsevier Science.)...

P. McConnell, and C. G. Brouillette, Bioorg. Med. Chem. Lett., 10, 2427 (2000). Stereoselective Binding of an Enantiomeric Pair of Stromelysin-1 Inhibitors Caused by Conformational Entropy Factors. 

In this context, it should be pointed out that CE is also an appropriate tool to determine stereoselectively binding constants between SAs and SOs 4.484-487. ... 

The ability of proteins to stereoselectively bind small molecules has been used to develop a series of commerdally available protein-based CSPs (the type V HPLC CSPs), including phases that contain immobilized AGP (84), HSA (85), BSA (86), and ovomucoid (OVM) (87) (see Table 5). All these CSPs are useful in the HPLC resolution of enantiomeric compounds and appear to have an extremely wide range of applications, and the AGP CSP seems to have the broadest utility of any of the current CSPs (9-11). However, although the type V CSPs display high enantioselectivities, they also have low capadties due to the relatively small amounts of the chiral selector that can be immobilized per g silica. Thus, these CSPs are useful... 

Possible mechanisms responsible for this stereoselective renal clearance of pindolol appear to be stereoselective renal metabolism or stereoselective renal secretion (stereoselective binding to plasma proteins was not observed). Recently, Somogyi et al. investigated the effect of coadministration of dmetidine on the renal clearance of the two enantiomers of pindolol (58). Cimetidine significantly reduced the renal clearance of both enantiomers, but reduced the renal clearance of the R enantiomer by a greater extent than the S enantiomer. These data are consistent with the stereoselective renal elimination mechanism for pindolol, with the S enantiomer being preferentially cleared. 

C. Lagercrantz, T, Larsson, and I. Denfors, Stereoselective binding of the enantiomers of warfarin and tryptophan to serum albumin from some different species studies by affinity chromatography on columns of immobilized serum albumin. Comp. Biochem. Physiol, 69C 375 (1981),... 

S. Iwakawa, H. Spahn, L. Z. Benet, and E. T. Lin, Stereoselective binding of the glucuronide conjugates of carprofen enantiomers to human serum albumin, Biochem. Pharmact., 39 949 (1990). 

N. Muller, C, Wioland, E Lapicque, C. Monot, E. Payan, R. Dropsy, and P, Netter, Stereoselective binding of etodolac to human serum albumin, 2nd International Symposium on Chiral Discrimination, Rome, 1991. 

I. Fitos, Z. Tegyey, M. Simonyi, J. Sjfiholm, T. Larsson, and C. Lagercrantz, Stereoselective binding of 3-acetoxy and 3-hydroxy l,4-benzodiazepin-2-ones to human serum albumin, Biochem. Pharmacol., 35 263 (1986). 

I. Fitos, M. Simonyi, Z. Tegyey, L. Otvos, J. Kajtar, and M. Kajtar, Resolution by affinity chromatography Stereoselective binding of racemic oxazepam esters to human serum albumin, /. Chmmatogr., 259 494 (1983). 

M. Simonyi, 1. Fitos, J. Kajtar, and M. Kajtar, Application of uitrafiltration and CD spectroscopy for studying stereoselective binding of racemic U-gands, Biochem. Bio tys. Res. Commun., 109 851 (1982). 

M. Simonyi, I. Fitos, Z. Tegyey, and L. Otvos, Stationary uitrafiltration a radio-tracer technique for studying stereoselective binding of racemic ligands, Biochem. Biof ys. Res. Commun., 97 1 (1980). 

I, Fitos, M. Simonyi, and Z. Tegyey, Resolution of warfarin via enhanced stereoselective binding to human serum albumin induced by lorazepam acetate. Chromatography 87 (H. Kalasz and L. S, Ettre, eds.), Akademiai Kiado, Budapest, 1988, p. 205,... 

E Albani, R. Riva, M. Contin, and A. Baruzzi, Stereoselective binding of propranolol enantiomers to human ot, acid glycoprotein and human plasma, Br. /. Clin. Pharmacol., 18 244 (1984). 

H. J. Zhou, S. D. Shay, and A. J. J. Wood, Ethnic diffetettces in stereoselective binding of propranolol, Clin. Pharmacol. Ther., 49 177 (1991). 

Walle, U.K. Walle, T. Bai, S.A. Olanoff, L.S. Stereoselective binding of propranolol to human plasma, al-acid glycoprotein and albumin. Clin. Pharmacol Ther. 1983, 34 (6), 718-723. 

Andrisano, V. Bertucci, C. Cavrini, V. Recatini, M. Cavalh, A. Veroli, L. Fehx, G. Wainer, I.W. Stereoselective binding of 2,3-suhstituted 3-hyrox3fpropionic acids on an immobilized human serum albumin chiral stationary phase. Stereo-chemical characterisation and quantitative structure-retention relationship study. J. Chromatogr., A 2000, 876, 75-86. 

Analyzing Eq. (1), one realizes that when the requirement Kk + Kg is not necessary for obtaining A/x 0. This means that in CE, a chiral recognition in the classical meaning of this definition Kk + Kg) is not always necessary for a chiral separation. This is theoretically feasible but has not been undoubtedly evidenced yet experimentally. More common is the case when ixqr = ixc,s and then Kk + Kg is the necessary requirement for enantioseparation. A combined contribution of both a stereoselective binding of the enantiomers to a chiral selector Kk Ks) and a mobility difference between the transient di-astereomeric complexes ixqr + mc,s) is also possible. 

Procedure 8.5 Stereoselective Binding of Cr(phen)3]3+ to DNA Studied by Equilibrium Dialysis and CD Spectroscopy15... 

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