Application of the NMR spectroscopy in the structural analysis of clonidine

Abstract

NMR spectroscopy is one of the most powerful techniques available for studying the structure of molecules. It involves the absorption of radioawaves by the nuclei of some combined atoms (: 1H, 13C, 15N, 19F, 3 IP) in a molecule that is located in a magnetic field. Nuclear magnetic resonance spectroscopy is the use of the NMR phenomenon to study physical, chemical, and biological properties of matter. The most important applications are proton NMR and carbon-13 NMR spectroscopy. In principle, NMR is applicable to any nucleus possessing spin. This property of nucleis to have a spin, was used to establish the structure of clonidine using 1H and 13C spectrum. Clonidine-N-(2,6-dichlorophenyl)-4,5-dihydro-lH-imidazol-2-amine- treats high blood pressure by stimulating ?2 receptors in the brain, which decreases cardiac output and peripheral vascular resistance, lowering blood pressure. It has specificity towards thepresynaptic ?2 receptors in the vasomotor center in the brainstem. This binding decreases presynaptic calcium levels, and inhibits the release of norepinephrine (NE). The net effect is a decrease in sympathetic tone. Was determinated : • the number of carbon atoms using 13C spectrum(DMSO), and their shift's, ppm : 158.5(C7), 134.5(C8), 129.7(C9), 131.5(C10), 129.7(C11), 130.5(C12). • the number of hydrogen atoms using 1H spectrum(DMSO), and thei shift's, ppm : 7.58(H9), 7.46(H10), 7.58(H11), 10.72(H6), 8.5ЦН1), 43.2(2H4d, 2H5d). The obtained spectrum gave us the possibility to establish the spatial structure of the analyzed sample. The impact of NMR spectroscopy on the natural sciences has been substantial. It can, among other things, be used to study mixtures of analytes, to understand dynamic effects such as change in temperature and reaction mechanisms, and is an invaluable tool in understanding protein and nucleic acid structure and function. It can be applied to a wide variety of samples, both in the solution and the solid state.