Antibacterial and Antioxidant Activity Evaluation of Bis-Substituted İsovanillin Derivatives

Herein, a series of twelve bis-hydrazone substituted isovanilline derivatives 3(a-l), were freshly re-synthesized by the reaction of bis-aldehydes with substituted hydrazide derivatives since these compounds previously showed potent aldose reductase inhibition properties. The obtained compounds were tested for their potential antibacterial and antioxidant activities. In the present study, four different bacterial strains were used, including Gram-positive (Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212) and Gram-negative (Pseudomonas aeruginosa ATCC 10231, Escherichia coli ATCC 25912). On the other hand, the antioxidant capacities of freshly re-synthesized bis-hydrazone substituted isovanilline derivatives were determined by using several antioxidant methods, including DPPH free radical scanvenging, TEAC cupric reducing (CUPRAC) and metal chelating activity methods. Several lead molecules were discovered as a potential bacterial inhibitors against S. aureus and E. coli bacterial strains. More specifically, compounds 3g (R=-H) and 3j (R=-4Cl) showed great inhibition properties against E. coli bacterial strains by having MIC values of 1.56 and 6.25 µg/mL, respectively. Moreover, none of the compounds showed potent antioxidant activity against tested methods with respect to compared standards.