The effects of structural changes on the anti-microbial and anti-proliferative activities of diimidazolium salts

An array of diimidazolium salts has been synthesized and used to investigate their anti-microbial andanti-proliferative activities. In particular, salts based on the 3,30-di-n-alkyl-1,10-(1,n-phenylenedimethylene)-diimidazolium cation and differing in the alkyl chain length on the imidazolium ion, the isomericsubstitution on the aromatic spacer and in the anion nature were used. The anti-proliferative activity wasevaluated against cervical (HeLa), colon adenocarcinoma (HT-29) and breast (SKBR3) cancer cell lines. Inthe latter case, also a morphological assessment after treatment with salts was performed. All salts weretested for their hemolytic activity against human erythrocytes. On the other hand, the anti-microbialactivity was investigated using both Gram-negative (Escherichia coli) and Gram-positive (Kokuria rhizophila,Staphilococcus aureus and Bacillus subtilis) strains. On the whole, the data collected demonstrate thatbiological activity is the result of the combined action of both cation and anion structures. In general, thecation hydrophobicity plays the most significant role with structural features of the anion becoming morerelevant in the presence of a shorter alkyl chain on the cationic head.