Synthesis, Characterization and Antifungal Activity of Manganese (II) Complex with Schiff Base Derived from Acetylacetone and Leucine

This study was aimed at synthesizing, characterizing and evaluating the antifungal activity of the Schiff base and Mn (II) complex. The reaction of the mixture of ethanol solution of acetylacetone and leucine yielded a Schiff base. The interaction between the Schiff base in hot aqueous methanol mixture and manganese (II) chloride in ethanol gave the manganese (II) Schiff base complex. The complex was characterized by decomposition/melting point temperatures, solubility test, IR spectrophotometry, colour determination, dissociation constant of Schiff base and antifungal activity. The Schiff base obtained has yellow colour, with a melting point of 250°C and percentage yield of 54.67% while the manganese (II) complex obtained had a pink colour with decomposition temperature of 167°C and percentage yield of 76.40%. The Schiff base and the complex was soluble in some solvents but slightly soluble in others. The Infrared spectra of the Schiff base showed a band at a range of 1600cm -1 - 1622cm -1 attributed to v (C=N) stretching frequencies establishing it being a Schiff base. Similar bands were observed in the spectra of Manganese (II) Schiff base complex but in lower frequencies indicating that the Schiff base has coordinated to the Mn ion. The antifungal activity of manganese (II) complex showed significant activity on the fungal isolates Candida albican and Sacchromyces cerevisiae. The study concludes that Schiff base synthesized was a weak acid and the Schiff base was not an active drug against the fungal pathogens used but Mn (II) complex was active against the pathogens used.