Chiral recognition based on enantioselective interactions of propranolol enantiomers with cyclosophoraoses isolated from Rhizobium meliloti.
Cyclosophoraoses isolated from Rhizobium meliloti, as an NMR chiral shift agent, were used to discriminate propranolol enantiomers. Continuous variation plot made from the complex of cyclosophoraoses with propranolol showed that the diastereomeric complex had predominantly 1:1 stoichiometry through UV spectroscopic analysis. The chiral recognition of propranolol enantiomers by cyclosophoraoses was investigated through the determination of binding constant based on the (13)C NMR chemical shift changes. The averaged K(obs) values from the plots were 55.7 M(-1) for (R)-(+)-propranolol and 36.6 M(-1) for (S)-(-)-propranolol, respectively. Enantioselectivity (alpha = K(R+)/K(S(-)) of 1.52 was then obtained. Computational calculation also revealed that (R)-(+) propranolol was more tightly bound with cyclosophoraose than (S)-(-)-propranolol due to the enhanced van der Waals interaction.
Lee
Sanghoo
S
Department of Microbial Engineering, and Bio/Molecular Informatics Center, Konkuk University, 1 Hwaynag-dong Gwangjin-gu, Seoul 143-701, South Korea.
Choi
Youngjin
Y
Lee
Sangsan
S
Jeong
Karpjoo
K
Jung
Seunho
S
D001665:Binding Sites; D003198:Computer Simulation; D005936:Glucans / Q000302:isolation & purification; D008958:Models, Molecular; D009010:Monte Carlo Method; D019906:Nuclear Magnetic Resonance, Biomolecular; D009844:Oligosaccharides / Q000302:isolation & purification; D011433:Propranolol / Q000737:chemistry* / Q000302:isolation & purification*; D016962:Sinorhizobium meliloti / Q000737:chemistry; D013237:Stereoisomerism; D013816:Thermodynamics; D047071:beta-Glucans
D005936:Glucans; D009844:Oligosaccharides; D047071:beta-Glucans; C080135:cyclic beta(1-2)glucan; D011433:Propranolol