title: Complementary hydrogen bonding of a carboxylato-barbiturate with urea and acetamide: experimental and theoretical approach.
abstract: A barbiturate derivative, 4-(2,4,6-trioxo-tetrahydro-pyrimidine-5-ylidenemethyl)-benzoic acid (L1) possessing functional complementarity to amides has been synthesized and characterized. Its binding separately with urea and acetamide was monitored using UV-vis, fluorescence and (1)H-NMR spectroscopic titrations. Experiments suggested stronger binding of L1 with urea as compared to acetamide. The solid adducts of L1 prepared separately with urea and acetamide were also characterized using IR, (1)H-NMR spectral and PXRD techniques. Theoretical studies on hydrogen bonded complexes of L1-urea and L1-acetamide in the gas phase, aqueous, and DMSO medium were carried out using density functional theory (DFT) at the B3LYP/6-31G** level. The theoretical calculations agreed to the experimental results.
authors.affiliation: Department of Chemistry, Faculty of Science, Banaras Hindu University, Varanasi, India.
authors.forename: Md Amin
authors.initials: MA
authors.lastname: Hasan
authors.forename: A
authors.initials: A
authors.lastname: Seshaditya
authors.forename: Stanislav
authors.initials: S
authors.lastname: Záliš
authors.forename: Lallan
authors.initials: L
authors.lastname: Mishra
mesh_terms: D000081:Acetamides / Q000737:chemistry*; D001463:Barbiturates / Q000737:chemistry*; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D011789:Quantum Theory; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D014508:Urea / Q000737:chemistry*
chemical_list: D000081:Acetamides; D001463:Barbiturates; D014508:Urea; C030686:acetamide; C032232:barbituric acid