Highlighting the possible secondary interactions in the role of balhimycin and its analogues for enantiorecognition in capillary electrophoresis |
| |
Authors: | Zhengjin Jiang Zhuohong Yang Roderich D Süssmuth Norman Williams Smith Shuting Lai |
| |
Institution: | 1. Department of Pharmacy, King''s College London, SE1 9NH, London, UK;2. College of Science, South China Agriculture University, 510642, Guangzhou, China;3. Institute for Chemistry, Technical University Berlin, Strasse des 17, Juni 135, D-10623, Berlin, Germany |
| |
Abstract: | It is believed that the enantiorecognition mechanism based on macrocyclic antibiotics involves multimodal interactions via hydrogen bonding, π–π interaction, steric hindrance, hydrophobic interaction and so on. A variety of enantiomeric N-benzoylated amino acids were separated using balhimycin (A) or its analogues bromobalhimycin (B) and dechlorobalhimycin (C) as chiral mobile phase additive using a CE method, which combined the partial filling technique with the dynamic coating technique and the co-EOF electrophoresis technique. The enantioresolution and the migration time were highly relevant to the structure of analytes, especially to the substitutions on the N-tagged benzoyl moiety of the amino acids. A steric effect and π–π interaction based mechanism is proposed in order to explain some observed enantioresolution differences between positional isomers. Notably dechlorobalhimycin exhibited the best enantioresolution for several N-benzoylated derivatives of leucine, which was rarely observed for N-dansylated amino acid derivatives. The hydrophobicity difference of the aglycone pocket among three chiral selectors was assumed to account for this behaviour. |
| |
Keywords: | Capillary electrophoresis Enantioseparation Balhimycin Glycopeptide antibiotics N-Benzoylated amino acids |
本文献已被 ScienceDirect 等数据库收录! |
|