title: Estimation of the ionization pK(a) of pharmaceutical substances using the computer program Sparc.
abstract: The computer program sparc was used to calculate the pK(a) values of some important pharmaceutical substances. The sparc models proved to be suitable for estimating the pK(a) values of beta-adrenergic blocking agents and benzodiazepine drugs. Ionization macroconstants, microconstants, zwitterionic equilibria, speciation curves as a function of the pH and the isoelectric points of a semi-essential amino acid, arginine, and an anti-inflammatory, niflumic acid, were calculated.
authors.affiliation: Environmental Research Laboratory, U.S. Environmental Protection Agency, Athens, GA 30605, USA.
authors.forename: S H
authors.initials: SH
authors.lastname: Hilal
authors.forename: Y
authors.initials: Y
authors.lastname: El-Shabrawy
authors.forename: L A
authors.initials: LA
authors.lastname: Carreira
authors.forename: S W
authors.initials: SW
authors.lastname: Karickhoff
authors.forename: S S
authors.initials: SS
authors.lastname: Toubar
authors.forename: M
authors.initials: M
authors.lastname: Rizk