Enantiomeric discrimination of chiral organic salts by chiral aza-15-crown-5 ether with C1 symmetry: experimental and theoretical approaches
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Tarih
2015
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Springer
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
The work involves an experimental (H-1 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 (88-1,389 M-1), with phenylalanine being more discriminated. The difference in experimental binding free energies (Delta G(R) - Delta G(S)) for alanine, phenylalanine and valine enantiomers were calculated as -0.36, -1.58 and 0.80 kcal mol(-1), respectively. The differences in theoretical binding energies were calculated by MM-PBSA (Delta E-PB(R) - Delta E-PB(S)=) 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 1.66 kcal 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.
Açıklama
Anahtar Kelimeler
Enantiomeric Discrimination, Chiral Aza-Crown Ether, Molecular Recognition, Amino Acid Ester Salt, H-1 Nmr Titration, Computational Calculation, Molecular Dynamics, Mm-Pbsa, Dft
Kaynak
Journal of Molecular Modeling
WoS Q Değeri
Q3
Scopus Q Değeri
Q2
Cilt
21
Sayı
3
