Artificial flavin receptors: effects of hydrogen bonding on redox properties of a flavin mimic.
This review describes the roles of hydrogen bonding on the redox properties of a flavin mimic by using artificial flavin receptors. The receptors exploited are melamine derivatives bearing guanidinium ion(s) that strongly bind 6-azaflavin through five or seven hydrogen bonds involving N(1), C(2)=O, N(3)-H, C(4)=O, N(5), and N(6) positions in CHCl3 and CHCl3-acetonitrile. It has been shown that receptors are quite useful for examination of the hydrogen bonding effects on the redox potential, stability of the anionic semiquinone radical, and the oxidation activity of 6-azaflavin. The functionalized receptors have a substrate- or a metal-binding site have been shown to facilitate the reactions by forming the noncovalent assemblies. A possibility as an apoprotein model of the receptors has been mentioned also.
Yano
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Department of Chemistry, Gunma University, Kiryu, Japan. yano@chem.gunma-u.ac.jp
D001665:Binding Sites; D005415:Flavins / Q000737:chemistry*; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008956:Models, Chemical; D010084:Oxidation-Reduction; D011725:Pyridines / Q000737:chemistry*
D005415:Flavins; D011725:Pyridines