Design, Synthesis and Spectroscopic Characterizations of Medicinal Hydrazide Derivatives and Metal Complexes of Malonic Ester

Abstract

Background: A new series of malonic acid-based hydrazide derivatives (BPMPDH, 2HPMPDH, 3HPMPDH, 4HPMPDH, DMPDH) are successfully synthesized by the reaction of malonic ester hydrazide with various substituted aldehydes like salicylaldehyde, benzaldehyde, 4-hydroxy benzaldehyde, 3-hydroxy benzaldehyde and formaldehyde) Methods: metal complexes of prepared hydrazide derivatives were prepared using metals like Cu+2, Zn+2 and Ni+2 via a mild, efficient and convenient method. Newly synthesized compounds were characterized by IR, NMR (1H & 13C), UV/VIS and mass spectrometry. The presence of –C=N- peak at 1600-1700 cm-1 with the absence of NH2 peak at 3500 cm-1 in FTIR spectra. In 1HNMR peak at, 11.00-13.00 ppm for –OH protons and 7.00-9.50 ppm for –NH verified the synthesis of new hydrazide derivatives. The presence of a C-OH sharp peak at 180-190 ppm, a C=O peak at 160-170 ppm and a C=N peak at 140-150 ppm confirmed synthesis. In mass spectra, the molecular ion peaks at 308 m/z, 340 m/z and 156 m/z confirmed synthesis. Synthesized compounds have also been analyzed for their antioxidant, antibacterial, antifungal, chymotrypsin and tyrosinase inhibition activities Result and Conclusion: The results revealed that the 2HPMPDH, 3HPMPDH, 4HPMPDH and their Cu+2 and Zn+2 metal complexes showed more successful inhibition against standard drugs, based on structure activity relationship.