title: A study of the intermolecular interactions of tolmetin/N-acetyl-L-tyrosine ethyl ester complex.
abstract: The formation of tolmetin/N-acetyl-l-tyrosine ethyl ester (ATEE) complex has been reported by means of both theoretical and experimental studies, including quantum mechanical calculations as well as UV-vis absorption, fluorescence and time-resolved spectroscopy measurements. It has been found that the fluorescence of ATEE is quenched due to the formation of a non-fluorescent complex between ATEE and tolmetin in the ground state. The geometrical parameters of ATEE/tolmetin complex have been determined with the use of the DFT method applying the B3LYP correlation-exchange functional and 6-31G(d) basis set. The results of experiments indicated the static ATEE quenching by tolmetin. Additionally, the experimental and theoretically predicted Gibbs free energy of complexation has been calculated.
authors.affiliation: Natural Science Department, University of Houston-Downtown, One Main Street, Houston, TX 77002, USA. tito1902000@yahoo.com
authors.forename: Antonio
authors.initials: A
authors.lastname: Tito
authors.forename: Claudia
authors.initials: C
authors.lastname: Jimenez-Lopez
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Kowalska
authors.forename: Stanisław
authors.initials: S
authors.lastname: Wysocki
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry*; D016861:Cyclooxygenase Inhibitors / Q000737:chemistry; D015394:Molecular Structure; D013057:Spectrum Analysis; D014046:Tolmetin / Q000737:chemistry*; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D016861:Cyclooxygenase Inhibitors; D014443:Tyrosine; C007651:ethyl N-alpha-acetyl-tyrosinate; D014046:Tolmetin