Schiff bases

Imidazo [1, 2-a] pyridine based Schiff bases have been synthesized by condensing different 3-aryl-5-methyl isoxazole hydrazides with 2-aryl imidazo [1, 2-a] pyridine carbaldehydes by following hybridization approach. The structures of newly synthesized Schiff bases have been characterized by spectral data and elemental analysis. In In vivo anti-inflammatory screening, compounds 4b & 4f showed significant activity and the results are comparable with the standard drug, diclofenac. None of the compounds exhibited significant activity in anti-bacterial study. The work might result in the emergence of new series of compounds with potent anti-inflammatory activity.

Quinolines are a class of heterocyclic compounds, widely present in nature as quinoline alkaloids. Compounds having 2-quinolone moiety are associated with interesting biological activities such as antimalarial, tuberculostatic, antibacterial, antiviral, antifungal, anticancer, antidiabetic, cardiotonic and bronchodilator activity etc. The present work deals with the synthesis, characterization of substituted 7-amino-4-methyl-2-quinolone. The synthesized compounds were characterized by the IR, 1H-NMR & Mass spectral studies. Out of 10 test compounds evaluated for their antibacterial activities, four test compounds 3,6,8 & 9 were found to be active against Bacillus subtilis while amoxycillin and gentamycin were used as standard.

Schiff bases represent an important class of organic compounds owing to their wide range of biological activities and industrial applications. They are characterized by the presence of azomethine group and formed by the condensation of primary amines with aldehydes or ketones. They also serve as a back bone for the synthesis of various heterocyclic compounds. Since last few decades, a variety of Schiff bases and their derivatives have been synthesized and reported to possess a wide variety of biological activities i.e. anticancer, antioxidant, antiglycation, antimicrobial, antimalarial, antiviral and CNS activities. This review highlights the synthetic strategies of novel Schiff bases of different heterocycles and their evaluation for different CNS activities. 

Fifteen new Fluorine substituted Schiff bases were prepared by condensation of different substituted benzaldehyde with 4-fluoroaniline. The structures of these Schiff bases have been confirmed by IR, 1H NMR, mass and elemental analysis. All the new compounds synthesized have been evaluated for their action against bacteria and fungi. Key words: Schiff bases, 4-fluoroaniline, substituted benzaldehyde, antimicrobial activity.