MICROWAVE ASSISTED SYNTHESIS OF NOVEL SCHIFF BASES AND THEIR BIOLOGICAL EVALUATION

Syed Shah Abdus Salaam* and Naziya Mehveen

ABSTRACT

The aim of present study is to synthesise novel thiazolodinones from schiff bases of salicyladldehyde by microwave assisted method. The literature review showed that schiff bases possess a wide spectrum of biological activities such as antibacterial, anti tubercular, anti inflammatory, antiviral and antioxidant activity. Schiff bases of salicylaldehydes have also been reported as plant growth regulator and antimicrobial or antimycotic activity. Thiazolidinones found to have a broad spectrum of pharmacological properties like anti HIV, antipsychotic, anticonvulsant and antitubercular activity. In the present study, Microwave was used to make chemical synthesis more environment friendly, safe, to improve the yield and also to reduce the time consumption. The newly synthesized Schiff bases (2a and 2b) were evaluated for anticoagulant activity. Schiff bases and thiazolidinones were purified, characterized and evaluated for antibacterial and anthelmintic activities. The yield of the synthesized compounds was found to be in the range of 70-86 %. All these molecules were characterized by physical data and FT-IR, 1H NMR and mass spectral analysis. The synthesized schiff bases (2a and 2b) at concentrations 10μg/ml, 20μg/ml, 40μg/ml and 80μg/ml were tested for anticoagulant activity using prothrombin time test. Time of coagulation for both the compounds was recorded and it was found out that Schiff base 2a showed better anticoagulant activity when compared to Schiff base 2b. All the synthesized compounds were tested for antibacterial activity on E.coli and S.aureus, using chloramphenicol as standard drug at concentrations of 0.1%, 0.2% and 0.3%. Amongst all the synthesized compounds, compounds 2a, and 3a showed highest activity. All the synthesized compounds were also screened for anthelmintic activity, using albendazole as standard. The compound 2a showed highest activity, 2b and 3a showed moderate activity.

Keywords: Microwave assisted synthesis, schiff bases, thiazolidinones, anthelmintic and antibacterial.