## 1 Introduction  
Nowadays, due to their diverse reactivity, pyridones have arisen as prominent constituents of various natural products and privileged pharmacophores in drug discovery [1]. 2-pyridones (2-hydroxypridine) and their derivatives represent a valuable \(N\)-heterocyclic building block of molecules with remarkable antibacterial [2, 3], antifungal [4], anti-inflammatory [5], antiviral [6] and anticancer [7] activities. In 2020, a 2-pyridone-based taczemetostat (TazveriKTM) was approved by the U.S. Food and Drug Administration as a drug for the treatment of epithelioid sarcoma, the first drug of its kind to inhibit the EZH2 enzyme [8]. The latest findings have identified 13 natural products containing 2-pyridone rings as inhibitors of the SARS-CoV-2 main protease, making them promising candidates in the treatment of COVID-19 [9]. Furthermore, 2-pyridone structures have emerged as suitable ligands in transition metal catalysis [10]. These compounds gain attention in technology-driven research areas due to their potential application in electronic organic devices, replacing traditional inorganic semiconductors [11]. Owing to the latest successes of 2-pyridone-based compounds in different fields, the chemistry of this valuable heterocyclic ring represents an important subject for future research and the development of new, more efficient compounds. In recent years, significant progress has been made in electroanalytical techniques for the detection of heterocyclic compounds of biological significance [12, 13, 14]. Moreover,the use of theoretical calculations is often employed along with experimental results in order to highlight the structure-electrochemical properties relationship and define the origin of electrochemical stability [15; 16; 17]. Although the physicochemical properties of the 2-pyridone ring have been studied extensively, reports on their electrochemical behavior are rare, hence the development of selective electrochemical sensors for their sensitive and selective detection. Among these, an electrochemical reduction of 1-benzylideneamino-4,6-diphenyl-2-pyridone and 1-amino-4,6-diphenyl-2-pyridone was conducted in an ethanolic BR buffer by applying polarography, CV with a hanging mercury drop electrode and controlled-potential electrolysis with a mercury pool electrode [18; 19]. Moreover, an electrochemical reduction of aldimines derived from 1-amino-4,6-diphenyl-2-pyridone and 1-benzylideneamino-4,6-diphenyl-2-pyridone in an ethanolic BR buffer was studied [18], as well as an electrochemical reduction of 1-amino-4,6-diphenyl-2-pyridone in an ethanolic buffer [19]. Although the oxidation of 2-pyridones has not been studied, a series of variously substituted 5-carboxy-6-methyl-3,4-dihydro-2(1H)-pyridone derivatives were electrochemically oxidized on a GC electrode, in a non-aqueous electrolyte, dry acetonitrile, by means of CV measurements. It was shown that all the investigated 3,4-dihydroxyproyridones underwent irreversible oxidation and that their derivatives were electrochemically oxidized to 2-pyridones, involving the removal of 2 electrons and 2 protons, which was confirmed by single crystal X-ray crystallography [20]. Also, the method of platinum electrodes by means of a rotating ring-disk electrode (RRDE) has been used for electrochemical oxidation of substituted 3,4-dihydroxyro-2-pyridones in anhydrous acetonitrile, wherein they were characterized by kinetic parameters. It was shown that the first stage of the electrochemical oxidation of substituted 3,4-dihydroxyro-2-pyridones corresponds to a two-electron process leading to the formation of the corresponding substituted 2-pyridones [21]. On the other hand, the electrooxidation of pyridones in aqueous electrolytes has not been studied so far. Considering the importance of 2-pyridone derivatives in various fields and encouraged by all the above statements, this work focused on the electrooxidation ability of nine pyridones (**1-9**, Figure 1) using CV and SWV in BR aqueous buffer solutions on a GC electrode.