SPECTROPHOTOMETRIC MONITORING OF THE OXIDATION OF THIOBENZAMIDE AT VARYING OXIDANT CONCENTRATIONS
Keywords:
oxidation, thioamide, UV-vis spectroscopy, pH.Abstract
The metabolism of substances with a thioamide group involves complex oxidation-reduction reactions, which is an important focus in modern pharmaceutical chemistry, so the thioamides act as key components in biologically active substances. Thioamides, with substituents that are aromatic, aliphatic, or heterocyclic, display a wide range of biological activities and include effects such as antimycobacterial, antibacterial, antifungal, antiviral, anticancer and anti-inflammatory properties. Understanding how thioamides behave during oxidation, is important for uncovering their metabolic pathways and for the design of new therapeutic medicaments. This study aim is the oxidation of thiobenzamide, and monitoring the oxidation flow were CrO3 is used as the oxidizing agent under various conditions. The oxidation products of thiobenzamide were obtained according the literature data and all of the products were used in further oxidation reactions. Experiments were conducted to optimize the reaction parameters and to examine how oxidant concentration affect the reaction pathway. The oxidation reactions were carried out in different mediums, acidic media (KCl/HCl), neutral and alkaline phosphate buffer (pH 7 to 10). To understand how the concentration of oxidant impact the reaction flow, systematically was varied the substrate and oxidant molar ratios at 1:1, 1:5, and 1:10. The progress of the oxidation reaction was monitored directly from the reaction mixture using UV-Vis spectrophotometry. The results show a clear impact of pH and oxidation agent concentration on the reaction flow and the products of the reaction and they also highlight differences in the oxidation pathways under different medium as an acidic, neutral, or basic conditions. By changing the molar ratios of the oxidizing agent and the substrate, the best results were obtained at a molar ratio of 1:10, where majority of the substrate reacted and the best results are achieved at room temperature. Due to the low yield and rapid further reaction with thiobenzamide, some of the products cannot be isolated and detected and the composition of the reaction mixture changes over time. The products obtained during the reaction are stable under the specified experimental conditions. This study offers new insights into how thioamides behave during oxidation reaction with CrO3 and highlights the usefulness of spectroscopic and chromatographic techniques for tracking changes in thioamides. The findings enhance our understanding of chemistry of thioamides and provide useful information for designing and evaluating biologically active compounds with antimycobacterial activity
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