title: 1H-NMR investigations on the hydrogen bond formation between the tranquilizers diazepam and nitrazepam and some nucleobases.
abstract: The formation of hydrogen bonds between the minor tranquilizers diazepam and nitrazepam and a few nucleobases was studied in deuterochloroform solution by means of proton magnetic resonance spectroscopy. The thermodynamic and spectroscopic data of the associations were evaluated on the basis of a dimer model, using the concentration dependent shifts of the protons involved in hydrogen bonds. The interactions of nitrazepam (deltaH0=-10 to -21 kJ/mol; deltaG025 -0.2 to -7.4 kJ/mol) were found to be stronger than those of diazepam (deltaH0=-10 to -13 kJ/mol; deltaG025=6.0 to 6.4 kJ/mol). The various binding sites of the benzodiazepines for hydrogen bonds are discussed.
mesh_terms: D000225:Adenine; D055598:Chemical Phenomena; D002621:Chemistry; D003975:Diazepam; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008433:Mathematics; D009567:Nitrazepam; D013329:Structure-Activity Relationship; D013816:Thermodynamics; D013941:Thymine; D014498:Uracil
chemical_list: D014498:Uracil; D009567:Nitrazepam; D000225:Adenine; D003975:Diazepam; D013941:Thymine