The synthesis of 3-{4'-[1'''-phenyl-3'''-(pyridin-3''''-yl)-1H-pyra-zol-4'''-yl]-2',3''-bipyridin-6'-yl}coumarins (5a-c); 3-{4'-[1'''-phenyl- 3'''-(pyridin-3''''-yl) -1H- pyrazol -4'''-yl ]-2',4''- bipyridin-6'-yl} coumarins (6a-c); 3-{4'-[1'''-phenyl-3'''-(pyridin-4''''-yl)-1H- pyrazol- 4'''-yl]-2', 3''- bipyridin-6' -yl}coumarins (7a-c) and 3-{4'-[1'''-phenyl-3'''-(pyridin-4''''-yl)-1H-pyrazol-4'''-yl]-2',4''-bi-pyridin-6'-yl}coumarins (8a-c) has been carried out by the reaction of 3-(3-(1-phenyl- 3-(pyridin-3-yl)-1H-pyrazol-4-yl)acryloyl)coumarins (1a-c) or 3-(3-(1-phenyl-3-(pyridin-4-yl)-1H-pyrazol-4-yl)acryloyl)coumarins (2a-c) with appropriate 3-pyridoyl methyl pyridinium iodide salt (3) or 4-pyridoyl methyl pyridinium iodide salt (4) in the presence of ammonium acetate in refluxing acetic acid respectively under Krohnke’s reaction condition. The required 3-(3-(1-phenyl-3-(pyridin-3-yl)-1H- pyrazol-4-yl)acryloyl)coumarins (1a-c) and 3-(3-(1-phenyl-3-(pyridin-3-yl)-1H-pyra-zol-4-yl)acryloyl)coumarins (2a-c) were prepared by the reaction of various 3-acetyl coumarins with 1-phenyl-3-(pyridin-3-yl)-1H-pyrazol-4-aldehyde and 1-phenyl-3-(pyridin-4-yl)-1H-pyrazol-4-aldehyde respectively in presence of catalytic amount of piperidine in refluxing ethanol. The 3-pyridoyl methyl pyridinium iodide salt (3) or 4-pyridoyl methyl pyridinium iodide salt (4) were prepared by the reaction of appropriate appropriate acetyl pyridine with iodine in dry pyridine in refluxing toluene. The structures of all the compounds synthesized, have been supported by analytical and spectral data. All the synthesized compounds were screened for their antimicrobial activity.