caa a22 4500 605512116 CHVBK 20210128100654.0 cr unu---uuuuu 210128e20150301xx s 000 0 eng 10.1007/s00894-015-2604-6 doi (NATIONALLICENCE)springer-10.1007/s00894-015-2604-6 Enantiomeric discrimination of chiral organic salts by chiral aza-15-crown-5 ether with C 1 symmetry: experimental and theoretical approaches [Elektronische Daten] [Safak Kocakaya, Yılmaz Turgut, Necmettin Pirinççioglu] The work involves an experimental (1H NMR) and theoretical (MD, MM-PBSA and DFT) investigation of the molecular recognition and discrimination properties of a chiral aza-15-crown-5 against methyl esters of alanine, phenylalanine and valine hydrochloride salts. The results indicate that the receptor binds enantiomers with moderate binding constants (88-1,389M−1), with phenylalanine being more discriminated. The difference in experimental binding free energies (ΔG R−ΔG S) for alanine, phenylalanine and valine enantiomers were calculated as −0.36, −1.58 and 0.80kcal mol−1, respectively. The differences in theoretical binding energies were calculated by MM-PBSA (ΔE R PB−ΔE S PB=) as −0.30, −1.45 and 0.88, by B3LYP/6-31+G(d) as −1.17, −0.84 and 0.74 and by M06-2X/6-31+G(d) as −1.40, −3.26 and 1.66kcal mol−1. The data obtained give valuable information regarding the molecular recognition mode of the organoammonium complexes of chiral aza-crown ether with C 1 symmetry, which may be relevant to biological systems. Graphical Abstract Left Superimposed lowest energy conformers of complexes of chiral aza-crown ether with theenantiomersof phenylalanineobtained from cluster analysis of MD trajectories. Right Non-linear dependence of 1H NMR chemical shifts of methyl groups of isopropyl in receptor 5 on the concentration of the enantiomers of valine ester salts Springer-Verlag Berlin Heidelberg, 2015 Enantiomeric discrimination nationallicence Chiral aza-crown ether nationallicence Molecular recognition nationallicence Amino acid ester salt nationallicence 1H NMR titration nationallicence Computational calculation nationallicence Molecular dynamics nationallicence MM-PBSA nationallicence DFT nationallicence Kocakaya Safak Department of Chemistry, Faculty of Science, University of Dicle, 21280, Diyarbakir, Turkey aut Turgut Yılmaz Department of Chemistry, Faculty of Science, University of Dicle, 21280, Diyarbakir, Turkey aut Pirinççioglu Necmettin Department of Chemistry, Faculty of Science, University of Dicle, 21280, Diyarbakir, Turkey aut Journal of Molecular Modeling Springer Berlin Heidelberg 21/3(2015-03-01), 1-13 1610-2940 21:3<1 2015 21 894 https://doi.org/10.1007/s00894-015-2604-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00894-015-2604-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kocakaya Safak Department of Chemistry, Faculty of Science, University of Dicle, 21280, Diyarbakir, Turkey aut NATIONALLICENCE 700 1- Turgut Yılmaz Department of Chemistry, Faculty of Science, University of Dicle, 21280, Diyarbakir, Turkey aut NATIONALLICENCE 700 1- Pirinççioglu Necmettin Department of Chemistry, Faculty of Science, University of Dicle, 21280, Diyarbakir, Turkey aut NATIONALLICENCE 773 0- Journal of Molecular Modeling Springer Berlin Heidelberg 21/3(2015-03-01), 1-13 1610-2940 21:3<1 2015 21 894