Synthesis, Characterization and Antimicrobial Evaluation of Symmetric Α-Diimine Schiff Bases Derived from Cis and Trans Racemic Mixture of Cyclohexanediamine

Abstract

From N,N'-bis(phenylmethylene)cyclohexane-1,2-diamine, substitution of a nitro group on each aromatic ring and its systematic displacement in the positions ortho, meta and para positions allowed to synthesize a homogeneous series of positional isomers. These four symmetric α-diimine Schiff bases derived from cis and trans racemic mixture of cyclohexanediamine have been characterized by conventional spectroscopic methods (NMR, IR and MS). Antimicrobial screening showed that, unlike N, N'-bis (phenylmethylene) cyclohexane-1,2-diamine, the bacterial strain Staphylococcus aureus CIP is sensitive to the other three compounds with MIC values of 93.75μg/ml, 187.5μg/ml and 375μg/ml. The Candida albicans fungal strain shows resistance to all synthesized compounds, but Candida glabrata is sensitive to the non-substituted N, N'-bis(phenylmethylene)cyclohexane-1,2-diamine and ortho substituted compound with a MIC value of 1500μg/ml.