Nuclear magnetic resonance ligand characteristics

Endogenous ligands for the cannabinoid receptor have not yet been identified. Arachidonylethanolamide, a new arachidonic acid derivative named anandamide, was isolated from porcine brain. Its structure was determined by mass spectrometry and nuclear magnetic resonance spectroscopy and was confirmed by synthesis. It inhibits the specific binding of a labelled cannabinoid probe to synaptosomal membranes in a manner typical of competitive ligands, and produces a concentration-dependent inhibition of the electrically-evoked twitch response of the mouse vas deferens, a characteristic effect of psychotropic cannabinoids. Similar compounds were synthesized and their pharmacological properties were investigated. 

Nuclear Magnetic Resonance Spectroscopy Nuclear Quadrupole Resonance Spectroscopy Rotational Sp roscopy Characteristic Vibrations of Compounds of Maiit-group Elements Vibrational Spectra of Transition-slement Compounds Vibrational Si ra of Some Co-ordinated Ligands Mossbauer Spectroscopy Gas-phase Molecular Structures Determined by Electron Diffraction. 

A characteristic of the magnetic resonance spectra of nitrosyl complexes is the presence of hyperfine interactions between the unpaired electrons and the nuclear spin of the nitrogen. The strength and orientation dependence of these interactions are determined by the geometry of the complex and the localization of unpaired electrons in ligand and metal orbitals. 

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