Synthesis and biological evaluation of new aryl substituted Schiff’s bases

Objective : Chemical substances employed to treat various infections caused by various types of microorganism are termed as antimicrobials and natural chemical compounds produced by specific types of bacteria are termed as antibiotics. Unlimited use of antibiotics in humans and animals and in areas other than the treatment and prophylaxis of disease have resulted in a serious problem of drug resistance. Various attempts have been adopted to cope with the resistance problem and enhance the activity, or broaden the spectrum of drugs . Based on structure-activity relationship synthesis of new compounds has been one of the best approaches for better results. It has been demonstrated that Schiff base of some leading molecules and antibiotics possess good potential as more effective and safe drugs. Encouraged by reports on potential of Schiff’s bases as antimicrobial agents and to cope up with the current requirements of developing newer, safer and broad spectrum agents attempts were made to synthesize new Schiff’s bases. Methods : Our earlier in which structure activity relationship studies revealed that substitution by nitro and amino gp in Schiff’s base moiety resulted in the enhancement of activity. So further attempts were made to extend the series with incorporation of nitro and amino moiety by condensing o,m dinitro substituted acid hydrazide with various nitro/amino substituted benzaldehydes for increasing their antimicrobial potential. Results : Synthesized compounds were characterized on the basis of spectral studies (like UV, IR, and NMR). All the synthesized derivatives were screened further for their antibacterial effect. All the synthesized derivatives were screened further for their antibacterial effect. Conclusions : Highest activity was observed in the derivative with nitro substitution in both the aryl rings.