title: 8-Fluoro-8-demethylriboflavin as a potential active-site-directed reagent for flavoprotein. Reaction with some amino acids.
abstract: 8-Fluoro-8-demethylriboflavin was shown to be a potential active-site-directed reagent for flavoproteins. It reacted with the nucleophiles of N-acetylcysteine (-SH), N-acetyltyrosine (-OH), alpha-N-acetyllysine, and glycine (epsilon- and alpha-NH2, respectively) under fairly mild conditions, and the reaction products were identified. The reactivity of the fluoroflavin was higher than that of 8-chloro-8-demethylriboflavin, which reacted only with the cysteine derivative among the amino acid derivatives used, and whose pseudo first order rate constant at 23 degrees C was 1/23 of that of the fluoroflavin. The reactivity of the fluoroflavin was also estimated by 13C and 19F NMR spectroscopy. The results showed that this compound is more reactive than the chloroflavin.
mesh_terms: D000596:Amino Acids; D001665:Binding Sites; D005420:Flavoproteins / Q000378:metabolism*; D007700:Kinetics; D011485:Protein Binding; D012256:Riboflavin / Q000031:analogs & derivatives / Q000494:pharmacology; D013053:Spectrophotometry; D013329:Structure-Activity Relationship
chemical_list: D000596:Amino Acids; D005420:Flavoproteins; C037198:8-fluoro-8-demethylriboflavin; D012256:Riboflavin