4-(2-(1-(4-aryl-3-(furan-2-yl(hydroxy)methyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carbonyl)-3-methyl5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-N-(thiazol-2-yl) benzene sulphonamides (2a-e) were synthesised by condensation of 4-(2-(1-(4-aryl-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carbonyl)-3-methyl-5-oxo-1Hpyrazol-4(5H)-ylidene) hydrazinyl)-N-(thiazol-2-yl) benzene sulphonamide (1a-e) with furfuraldehyde. The structures of all the compounds (2a-e) were characterized duly. The compounds were also monitored for antimicrobial activity.

The nitrogen containing heterocycles are very important class of compounds in antileishmanial drug discovery. (1,2) Among them the pyrazole in different compounds shows diversified applications in different areas like technical, medical and agriculture field. They shows different pharmaceutical activity like antibacterial, antifungal, anticancer, antidepressant, antiinflammatory, anti- tuberculosis, antioxidant as well as antiviral agents (3,4). The fused derivatives of Pyrazole with another heterocyclic compounds studies for various pharmaceutical as well as biological activities (5,6). Pyrazolo [3,4-b] pyridine exhibit a broad variety of biological activities, like antimicrobial, insecticidal, anti- inflammatory, antineoplastic, anticonvulsant, antiparasitic, anti- fungal activities (7,8). Thus in continuous of our previous research work, it was thought to synthesised this type of fuse molecules. The present communication deals with the synthetic approach shown in scheme-1

The Schiff bases of (1a-e) isoniazid and 5-substituted- 2-furancarboxaldehydes on treatment with mercapto acetic acid yield, 4-thiazolidinone (2a-e) derivatives. These derivatives (2a-e) on Mannich base reaction with diphenyl amine and formaldehyde yielded the Mannich base products (3a-e). All the derivatives, (2a-e) and (3a-e) were characterized by elemental content and IR , NMR, LC-MS spectral data. All the derivatives have also been monitored for antibacterial activity.