Synthesis and Antioxidant Activity of Some New Binary Pyrazoles Containing Core Phenothiazine Moiety

α,β-Unsaturated ketones containing phenothiazine moiety 4, 5, and 7 were synthesized by condensation of 2-acetylphenothiazine (1) with different aryl aldehydes 2, 3 and dimethylformamide dimethylaceal. Pyrazoles 11, 18, 20, 22, 23, 24, 25, 26, 28, 29, 31, 32 and oxazole 34 skeletons were also synthesized by 1,3-dipolar cycloaddition reactions of α,β-unsaturated ketones with different nucleophilic reagents. Formylpyrazole derivative 36 was synthesized through Vilsmeier–Haack reaction of phenylhydrazone 35b. Newly synthesized compounds were screened for antioxidant activity. The data showed clearly that most of the compounds anchored to phenothiazine moiety displayed good antioxidant activity using ABTS method. Furthermore, compounds 11, 14, and 28 exhibited high protection against DNA damage induced by the bleomycin iron complex.