Determination of antioxidant capacities of 2,3-diaryl-benzothiophene derivatives that might have drug potential and analyse their effects on GST-α isozyme

Free radicals are molecules that contain one or more unconjugated electrons in their last orbitals. These molecules try to get the electron by taking electrons from other molecules to reach stable state. In doing so, the DNA damages the cell by causing unwanted oxidation reactions, such as protein modifications and lipid peroxidation. A defense system of the body that eliminates these harmful effects of free radicals is called antioxidant. Antioxidant molecules may be enzymatic, such as GSTs, or non-enzymatic such as ascorbic acid. In this thesis, two new 2,3-Diaryl-Benzothiophene derivatives, (3- (5-Bromo-thiophen-2yl) -1-ethyl-2-phenyl-1H-indole and 3- [2,2 '] bithiophenyl-5-yl-1-ethyl-phenyl-1H-indole), antioxidant capacities were determined by 5 different (DPPH, ABTS, Galvinoxyl, Phosphomolybdenum and FRAP method) antioxidant capacities method. Furthermore, their effects on GST A1-1 isozyme were investigated, as well. As a result of the study, antioxidant capacities of tested derivatives were seen from high to low in phosphomolybdenum, FRAP and ABTS methods, reciprocally. However, it was not determined any antioxidant activity by DPPH and galvinoxyl methods. In addition, both tested derivatives caused inhibition (compound 1 (25, 50 and 100 μM) and compound 2 (25, 100 and 250 μM)) and activation (compound 1 (1, 10 and 25 μM) ve compound 2 (1, 5 and 10 μM)) on GST A1-1 isozyme according to the applied concentrations.