Synthesis, characterization and biological activities of novel substituted formazans of 3,4-dimethyl-1H- pyrrole-2-carbohydrazide derivatives

Abstract Aim Synthesis of some novel formazan derivatives from condensation of aniline diazonium salt with a variety of Schiff bases of 3,4-dimethyl-1 H -pyrrole-2-carbohydrazide moiety and evaluate their potential antimicrobial and antioxidant activities. Methods Novel substituted formazans (2a-j) were prepared from Schiff bases of 3,4-dimethyl-1 H -pyrrole-2-carbohydrazide (1a-j) by condensation with aniline diazonium chloride in pyridine ( Scheme 1 ). All the formazan derivatives were characterized by IR, 1 H NMR, 13 C NMR and Mass spectroscopy. Results These molecules (2a-j) exhibits moderate to good antimicrobial and antioxidant activities some of which are comparable to standards used in this study. Conclusion The results of preliminary bioassays of derivatisation of Schiff bases to formazan indicate that a number of these molecules exhibits moderate to good antibacterial, antifungal and antioxidant activities some of which are comparable to standard used in this study. The outcome indicates that there is a good scope for evaluation of this class of compounds as potential leads towards antimicrobial and antioxidant agents.