Eco-friendly Synthesis of Some New Benzylidene-iminothiazolyl-pyrazol-3-ol Derivatives via One-Pot Multicomponent Reaction and Evaluation of Antioxidant Activities

In present work, one-pot multicomponent reaction (MCR) route for the synthesis of benzylideneiminothiazolyl- pyrazol-3-ol derivatives (5a-p) by reacting ethyl cyanoacetate (1), substituted benzaldehyde (2a-c), thiosemicarbazide (3) and substituted phenacyl bromide (4a-g). This reaction proceeds by using bleaching earth clay (BEC) (pH 12.5) in PEG-400 as a green reaction media. All the synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral data. The pharmacological investigation of the synthesized compounds suggest that most of them showed good antioxidant activity.