Abstract
Stereo-selective bindings of racemic propranolol with 2-adrenergic G-protein coupled receptor (2-AD-GPCR) in human plasma were studied by SPE-HPLC and verified by Gold docking software. Experimental results has shown 3.0% more binding of S-(-)-enantiomers in comparison to its R-(+)-antipode. The experimental results ascertained by Gold docking data. The interactions between ligands (propranolol enantiomers) and residues (amino acids of 2-adrenergic receptor sites) were calculated and the stabilities of their stereo-selective complexes were determined. The docking parameters calculated were bond lengths, binding energies, and Gold fitness scores. It has been observed that the stereo-selective fitting of S-(-)-propranolol on 2-AD-GPCR was about three times stronger (SPE-Chiral-HPLC=3.0%, ESER=0.30kcal/mol and GFSS-GFSR=3.31) than R-antipodes. The results presented have confirmed 8090 time more pharmaceutical potency of S-(-)-propranolol than its R-(+) counterpart. Efforts have also been made to conclude that the unbound amount of R-(+)-enantiomer (3.0%) bind with the precursors of insulin synthesis making cardiac patients diabetic too.