title: Interfacial behavior of uracil derivatives.
abstract: The adsorption of a number of methylated uracil derivatives and of 5-fluorouracil has been studied by surface electrochemical methods at a mercury electrode. All derivatives exhibit an initial or dilute adsorption region where they are adsorbed flat on the electrode surface and are bound by pi-electron overlap with the electrode. Uracil, thymine, 1,5-dimethyl-uracil, 5,6-dimethyluracil, 1,5,6-trimethyluracil and 5-fluorouracil undergo a surface reorientation from the initial flat solution activities for each compound. An unsubstituted N(3)-H group is an absolute requirement for a uracil derivative to be capable of adopting the perpendicular surface stance. In the perpendicular orientation the uracil derivative appears to be bound to the electrode primarily via a N(3)-H--(-) electrode bond although a similar but weaker hydrogen bond can be formed via the N(1)-H group for certain compounds.
authors.affiliation: Department of Chemistry, University of Oklahoma Norman, Oklahoma 73019, USA.
authors.forename: J G
authors.initials: JG
authors.lastname: Bake
authors.forename: S D
authors.initials: SD
authors.lastname: Christian
authors.forename: M H
authors.initials: MH
authors.lastname: Kim
authors.forename: G
authors.initials: G
authors.lastname: Dryhurst