Voltammetric Investigation of Inclusion Complexes of the Selected Succinimides with β-cyclodextrin and (2-hydroxypropyl)-β-cyclodextrin

Abstract

The inclusion complexes of the selected, potentially biologically active, succinimides with β-cyclodextrin (bCD) and (2-hydroxypropyl)-β-cyclodextrin (HPbCD) were prepared. the formation of the inclusion complexes of the investigated monophenyl and diphenyl succinimide derivatives was confirmed using attenuated total reflection (ATR) study. Their electrochemical behavior was examined by cyclic voltammetry (CV) and square wave voltammetry (SWV) in 0.05 M NaHCO₃ on a gold electrode. The stability constants for compound 1 were determined by cyclic voltammetry and calculated as K_bCD = 350.87 M^–1 and K_HPbCD = 250.67 M^–1. The SWV measurements reveal well defined peak at potential E_p = ~ 60 mV and the higher currents at E_p for both inclusion complex of the succinimides compared to the free compounds. The impact of chlorine atom in the phenyl moiety of succinimide derivatives on the activity in electrooxidation reaction is presented. Among the studied succinimides, according to SWV measurements, the most active is the monophenyl succinimide derivative (compound 1) in complex with bCD. The difference of peak current of compound 1 + bCD compared to compound 1 + HPbCD and free compound is 6.3 and 35.2 mA cm^–2, respectively.