title: Spectroscopic determination of acid dissociation constants of N-substituted-6-acylbenzothiazolone derivatives.
abstract: The acid dissociation constants of twelve novel drug precursor N-substituted-6-acylbenzothiazolone derivatives were determined by using the UV-vis spectroscopic technique. The protonation and deprotonation behaviors of the investigated molecules were researched from the super basic to super acid regions (i.e., 8 mol·L(-1) KOH to 98% H(2)SO(4)) including the pH region. It is observed that all of the molecules are protonated in the super acidic region. The calculated relative stability values of possible tautomer structures indicate that the keto form of investigated molecules is favored over the enol form. It was predicted that protonation occurs at the amide (oxo) group found in the keto form.
authors.affiliation: Department of Physics, Faculty of Arts and Sciences, Bitlis Eren University, Bitlis, Turkey. ygsidir@bitliseren.edu.tr
authors.forename: Yadigar Gülseven
authors.initials: YG
authors.lastname: Sıdır
authors.forename: Isa
authors.initials: I
authors.lastname: Sıdır
authors.forename: Halil
authors.initials: H
authors.lastname: Berber
mesh_terms: D000143:Acids / Q000737:chemistry*; D052160:Benzothiazoles / Q000138:chemical synthesis / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D013056:Spectrophotometry, Ultraviolet / Q000295:instrumentation; D013237:Stereoisomerism
chemical_list: D000143:Acids; D052160:Benzothiazoles