Exploring the Biological Perspective of Curcumin Inspired Dihydropyrazoles

Abstract

Pyrazoles are most explored and very important structural analogues of chalcones and have very special place in synthetic medicinal due to its pharmacological importance. Presence of pyrazole ring system in large number of naturally occurring molecules is one of the peculiar characteristics of this heterocyclic system. Inspired by excellent biological activity and structural complexity of pyrazole analogues we are working in area of chalcone and pyrazole synthesis. By reacting chalcone derivatives with phenylhydrazine, a library of novel dihydropyrazole compounds was created from well-designed Curcumin analogues. All the synthesized compounds were characterized by spectroscopic (1H and 13C NMR, IR spectra), spectrometric (Mass spectra) data and elemental analysis. Due to the presence of optically active carbon in the pyrazole ring, dihydropyrazoles exhibited the characteristic dd (double doublet). All of the synthesized compounds were tested for antifungal activity against six distinct fungal starins. With MIC (Minimum Inhibitory Concentration) values up to 3.12µg/ml., evaluated heterocyles exhibited strong inhibitory properties against the tested fungal strains. Antifungal activity was greatest in heterocyles containing nitro and methoxy modifications. SAR has been created between the numerous substitutions at the phenyl ring of produced heterocycles among 20 distinct derivatives assessed for biological activity.