Synthesis and Biological Activity of some New Ketonic and Phenolic Mannich Bases

Abstract

This study was aimed to the synthesis of some ketonic and phenolic Mannich bases . The biological activity of the targeted molecules are be evaluated. A General synthesis protocol was adopted, The active hydrogen component, formalin and a secondary amine were refluxed in ethanol for one hour to afford the Mannich base .In this way the following Mannich bases were synthesized: i) 1-hydroxymethyl-1-piperidinomethyl-2-naphthylacetate ii) 1,1-dimorpholinomethyl-2-naphthylactate iii) 1,1-dimethylaminomethyl-2-naphthylactate iv) 1,1-dimethylaminomethyl(2-aminophenyl)acetate v) 1,3-dibenzylidine-3-hydroxymethyl-1-morpholinomethylpropanone vi) 2-hydroxy-3,6-bis-dimethylaminomethylbenzoic acid vii) 2-hydroxy-bis-3,5-piperidinomethylbenzoic acid viii) 1-piperidinomethyl-3-phenylpropanone ix) 3,3-bis-piperidinomethylpentan-2,4-dione The targeted molecules were evaluated for their antimicrobial activity against six standard human pathogens and significant results were obtained. The biological activity of synthesized Mannich bases was adopted against four types of bacteria (+ve and –ve Gram stain) and two types of fungi. There micro organisms are: i) Bacillus subtilis (G+ve) ii) Escherichia coli (G-ve) iii) Staphylococus aureus (G+ve) iv) Pseudomonas aeruginosa (G-ve) v) Aspergillus niger (fungi) vi) Candida albicans (fungi) The synthesized Mannich bases which prepared from Salicylic acid and Acetophenone were showed higher biological activity against tested micro organisms by comparison with other synthesized Mannich bases.