Identification of interaction of 5-methoxy-isatin thiosemicarbazone derivatives with DNA and determination of their antimicrobial activities

Thiosemicarbazone and Thiosemicarbazides are used for wide range of biological applications. 5-MethoxyIsatin-3-(N-2-Fluorophenyl) Thiosemicarbazone + Zn (II), 5- Methoxyisatin-3-(N-4-Nitro phenyl) thiosemicarbazone + Z(II), 5- Methoxyisatin -3-(N-4-Fluoro phenyl) thiosemicarbazone + Zn(II), 5-Methoxyisatin-3- (N-2-Fluoro phenyl) thiosemicarbazone and 5-methoxyisatin-3 -(N-4-Fluoro phenyl) thiosemicarbazone were resynthesized by the reaction of 5-Methoxy isatin thiosemicarbazide derivatives. Antimicrobial activity and interaction of these compounds with CT-DNA were examined. Isatin thiosemicarbazones derivatives and their metal complexes were evaluated in in vitro conditions against to 16 different bacteria strains and one fungi strain. All compounds indicated antimicrobial activity against to S. aureus ATCC 25923, S. hominis and S. aureus ATCC, P. vulgaris, E. aerogenes ATCC 13048 and S. kentucky. It was also realized that ligand complexes of thiosemicarbazone affected greater number of bacteria strains than zinc complexes of thiosemicarbazone. Extension coefficient of isatin thiosemicarbazone derivatives was also calculated in this study. It was found that the increase in the concentration of all five compounds caused raising for absorbance of these compounds. The interaction of five compounds with calf thymus DNA were also investigated by using UV spectrophotometry. Kb values of all five compounds were calculated. All five compounds interacted with CT-DNA. 5- Methoxyisatin-3-(N-4-Nitro phenyl) thiosemicarbazone + Z(II) and 5-methoxyisatin-3 -(N-4-Fluoro phenyl) thiosemicarbazone caused an increase in absorbance with increscent concentration of CT-DNA. Other compounds showed opposite situation for CT-DNA interaction analysis. These compounds may be used for potential drugs or drugs additives based on their effects on microorganisms and DNA. Further studies should be required for evaluation of in vivo mode of action and toxicity of these compounds.