Discrimination of enantiomers of alpha-amino acids by chiral derivatizing reagents from trans-1,2-diaminocyclohexane.
New chiral derivatizing reagents (CDAs) derived from trans-1,2-diaminocyclohexane, having an electron-deficient aromatic substituent (either an aromatic imide or 3,5-dinitrobenzamide) and rigid structure (either an amide or a urea linker), are reported. Significant shift differences of diastereotopic protons in the 1H NMR signals are observed for enantiomers of suitably protected alpha-amino acids, linked to CDA by a covalent bond. A simple, general model rationalizing the observed enantiomer discrimination and based on semiempirical conformational search is presented.
Kaik
Magdalena
M
Department of Chemistry, A Mickiewicz University, 60780 Poznan, Poland.
Gajewy
Jadwiga
J
Grajewski
Jakub
J
Gawronski
Jacek
J
D000596:Amino Acids / Q000737:chemistry*; D003514:Cyclohexylamines; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D013237:Stereoisomerism
D000596:Amino Acids; D003514:Cyclohexylamines; D007202:Indicators and Reagents; C030435:1,2-cyclohexanediamine