Exploring the Functionality of Methyl Ketones in the Synthesis of New C X Bonds and Diverse Biologically Stimulating Heterocycles and Their Bio Application

Abstract

Heterocyclic systems are one of the most important classes of organic compounds present in nature or synthesized in the laboratory. These compounds possess an array of biological activities and are employed in the treatment of commonly occurring diseases. Literature survey revealed that chalcones possess a broad spectrum of biological activities like antimicrobial, anticancer, antimalarial, antidepressant, antihistaminic, antitubercular and anti-inflammatory, fluorescence, catalysis, chemosensor and as a photosensitizer. This thesis comprises the design and synthesis of novel chalcone derivatives and their sensing applications towards the detection of hydrazine hydrate and as potent biological applications, particularly as antibacterial agents. Hydrazine, as a toxic substance, seriously endangers human health and the environment. Based on the excellent luminescent properties, a simple but effective ratiometric fluorescent probe of chalcone derivative for the detection of hydrazine hydrate has been developed. The probe showed high selectivity and sensitivity towards hydrazine hydrate, and enabling good colorimetric detection of hydrazine hydrate by naked eyes. Synthesis and characterization of such compounds are confirmed based on IR, 1H NMR, 13C NMR and mass spectroscopy analysis. Chalcones afford a facile route of access to many of the heterocyclic systems containing nitrogen and oxygen. Hence, an attempt is made to synthesize chalcones from substituted aromatic/heterocyclic aldehydes and aryl methyl ketones by the conventional Claisen-Schmidt condensation. The resulting chalcones after purification and characterization by physical and spectral methods have been converted successfully into pyrazolines by reaction with phenyl hydrazine. The resultant compounds were identified by physical and spectral methods and were also screened for selected biological activities based on the reported literature. These efforts resulted in the synthesis of some promising compounds with significant biological activities.