Synthesis, antitubercular, antifungal and antibacterial activities of 6-substituted phenyl-2-(3'-substituted phenyl pyridazin-6'-yl)-2,3,4,5-tetrahydropyridazin-3-one.

A series of 6-substituted phenyl-2-(3'-substituted phenyl pyridazin-6'-yl)-2,3,4,5-tetrahydropyridazin-3-ones has been synthesized. An appropriate aromatic hydrocarbon reacts with succinic anhydride in presence of AlCl3 to yield beta-aroyl propionic acid. The corresponding acid was cyclized with hydrazine hydrate to give 6-(substituted aryl)-2,3,4,5-tetrahydro-3-pyridazinone, which was heated on steam bath with phosphorus(V) oxychloride to yield 3-chloro 6-substituted phenyl pyridazine. This intermediate after reaction with hydrazine hydrate was converted into 3-hydrazino-6-substituted phenyl pyridazine. The resulting product was converted into 6-substituted phenyl-2-(3'-substituted phenyl pyridazin-6'-yl)-2,3,4,5-tetrahydropyridazin-3-one by reacting with substituted aroyl propionic acid. Spectral data (IR, NMR, mass spectra) confirmed the structures of the synthesized compounds. The synthesized compounds were investigated for their in vitro antitubercular, antifungal and antibacterial activities. The results indicated that the synthesized compounds have mild to potent activities with reference to their appropriate reference standards.