Efficient enantiomeric analysis of primary amines and amino alcohols by high-performance liquid chromatography with precolumn derivatization using novel chiral SH-reagent N-(R)-mandelyl-(S)-cysteine.
Novel N-acylated-(S)-cysteine derivative-N-(R)-mandelyl-(S)-cysteine (R-NMC), containing additional chiral center, aromatic and polar alpha-substituents in contrast to the traditionally used enantiomerically pure thiols, has been demonstrated to be an efficient SH-reagent for enantiomeric HPLC analysis of primary nonfunctionalized amines and amino alcohols after precolumn derivatization with o-phthalaldehyde. The R-NMC-derived isoindoles as well as adducts formed using traditional SH-reagents had a characteristic absorption maximum at 340 nm with a molar absorbance 6000 M(-1) cm(-1), were stable during the HPLC-analysis and highly fluorescent allowing to detect 1 fmol of amino compound. Using diastereomeric R-NMC all tested amino alcohols were resolved effectively as well as nonfunctionalized amines, some of which were not resolved by a direct method on a chiral phase. Applying traditional enantiomeric N-acetyl-(S)-cysteine (NAC) only some isoindoles formed by aliphatic amino alcohols have been separated satisfactorily. The enhanced selectivity for R-NMC-derived isomers has been achieved, obviously, due to the involvement of the substituents at an extra chiral center into additional intramolecular interactions.
Guranda
Dorel T
DT
Faculty of Bioengineering and Bioinformatics, Belozersky Institute of Physicochemical Biology, Lomonosov Moscow State University, Russia.
Kudryavtsev
Pavel A
PA
Khimiuk
Andrei Y
AY
Svedas
Vytas K
VK
D000588:Amines / Q000032:analysis* / Q000737:chemistry; D000605:Amino Alcohols / Q000032:analysis* / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003545:Cysteine / Q000031:analogs & derivatives* / Q000737:chemistry; D013237:Stereoisomerism; D013439:Sulfhydryl Reagents / Q000737:chemistry*
D000588:Amines; D000605:Amino Alcohols; C506933:N-(R)-mandelyl-(S)-cysteine; D013439:Sulfhydryl Reagents; D003545:Cysteine