'Naked-eye' enantioselective chemosensors for N-protected amino acid anions bearing thiourea units.
Four linear thiourea anion receptors (1-3) derived from simple amino acid have been synthesized and their bonding properties with various chiral N-protected amino acid anions were examined by using UV-vis and fluorescence titration experiments. Receptors 1a, 2, and 3 exhibit excellent enantioselective recognition abilities towards N-Boc-protected alanine anion in the UV-vis spectra, obvious difference in the color of solution indicate that the enantiomers of N-Boc-alanine anion could be distinguished by naked eye directly. Receptor 1a is also found to carry out enantioselective fluorescent recognition of the N-acetyl-glutamate. (1)H NMR experiments suggest that hydrogen-bonding interaction between the host and guest is the main factor in the recognition process.
Qing
Guangyan
G
College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China.
Sun
Taolei
T
Chen
Zhihong
Z
Yang
Xi
X
Wu
Xiaojun
X
He
Yongbing
Y
D000042:Absorption; D000409:Alanine / Q000737:chemistry; D000596:Amino Acids / Q000032:analysis* / Q000737:chemistry*; D000838:Anions / Q000032:analysis / Q000737:chemistry; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D005971:Glutamates / Q000737:chemistry; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D009584:Nitrogen / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism; D013379:Substrate Specificity; D013890:Thiourea / Q000737:chemistry*
D000596:Amino Acids; D000838:Anions; D005971:Glutamates; D013890:Thiourea; C016195:N-acetylglutamic acid; D009584:Nitrogen; D000409:Alanine; D004121:Dimethyl Sulfoxide