Sulfonamides differing in the alkylamino substituent length – Synthesis, electrochemical characteristic, acid-base profile and complexation properties

Abstract

Two sulfonamide derivatives differing in the length of alkylamino substituent (NethylS and NpropylS) had been synthesized and then their structure and physicochemical properties were the subject of our extensive research. The complete spectroscopic and electrochemical profiles of studied compounds together with their ionic species assignment were established as well as reported. The electrochemical characteristics of sulfonamides were examined in both aqueous and aprotic solvents using cyclic voltammetry (CV) and differential pulse voltammetry technique (DPV). Furthermore, the pH effect on the NethylS/NpropylS redox processes and spectroscopic properties were also studied. The pKa values of compounds were determined using the combined pH-spectrophotometric (micro)titration method. The activity of studied sulfonamide antibiotics was verified by binding them into complexes with d-block metal ions, for which the complexing properties of both NethylS and NpropylS towards ruthenium(III) and rhodium(III) ions as well as their corresponding stability constants were determined.