Abstract
The reaction of 3-(3-amino-5-oxo-1,5-dihydropyrazol-4-ylidene)-1,3-dihydroindol-2-one with N-aryl-2-oxopropane hydrazonoyl chlorides in dioxane in the presence of triethylamine proceeded regio- and site selectively to give 3-(2-arylazo-3-methyl-6-oxo-imidazo[1,2-b]pyrazol-7-ylidene-indol-2-ones rather than the isomeric form 3-(3-arylazo-2-methyl-6-oxo-imidazo[1,2-b]pyrazol-7-ylidene-indol-2-ones. On the other hand, the reaction of N'-(2-oxoindoline-3-ylidene)hydrazinecarbothiohydrazide with hydrazonoyl chlorides in refluxing ethanol and in the presence of triethylamine proceeded regio- and site selectively to give the respective 3-(substituted-1,3,4-thiadiazol-2-ylidenehydrazono)indolin-2-ones. The mechanism of formation of the new products was also discussed. The structure assigned for the products was established by elemental and spectral data (H-1-NMR, IR, and Mass) and NOE experiment. Moreover, the biological activity of the products was evaluated against some fungi and bacteria, and the results obtained revealed the high potency of some of them compared with the used standard references.