NMR detection of intermolecular NH.OP hydrogen bonds between guanidinium protons and bisposphonate moieties in an artificial arginine receptor.
Hydrogen bonding plays a major role in the selective recognition of guanidinium groups by receptor molecules. The present NMR investigation provides direct experimental evidence of hydrogen bonds in an artificial arginine receptor complex consisting of alpha-N-benzoylarginine ethyl ester and a bisphosphonate tweezers molecule. trans-Hydrogen bond 2hJHP couplings between the phosphonate moieties and individual guanidinium protons as well as the amide proton have been detected by [1H,31P]-HMBC and [31P,1H]-INEPT experiments. The detected hydrogen bonding network in the investigated artificial arginine receptor shows a symmetrical end-on interaction of the guanidinium moiety, which enables concerted rotations and deviates from the structure proposed for the biological arginine fork.
Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Gerhard-Domagk-Str. 1, D-53121 Bonn, Germany. gschwind@uni-bonn.de
Ruth M
RM
Gschwind
Marcia
M
Armbrüster
Igor Z
IZ
Zubrzycki
D001120:Arginine / Q000737:chemistry* / Q000378:metabolism; D003080:Cold Temperature; D004164:Diphosphonates / Q000737:chemistry* / Q000378:metabolism; D019791:Guanidine / Q000737:chemistry* / Q000378:metabolism; D006860:Hydrogen Bonding; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods; D017459:Receptors, Amino Acid / Q000737:chemistry* / Q000378:metabolism
D004164:Diphosphonates; D017459:Receptors, Amino Acid; D001120:Arginine; D019791:Guanidine