The structure – Activity correlation in the family of dicationic imidazolium surfactants: Antimicrobial properties and cytotoxic effect

Imidazole and Imidazolium Antibacterial Drugs Derived from Amino Acids

“…The toxicity towards miscellaneous bacterial strains of alkyl imidazolium salts has been reported to increase with the length of the alkyl chain [57]. The monoimidazolium salts with these longer alkyl chains (1a-b and 3a-b) were more active against B. subtilis and E. coli than the bisimidazolium counterparts, with the monotopic salt 3b showing the lowest MIC and MBC values (entries 2 and 8, Table 1), this indicates that the introduction of two hydrophobic alkyl chains contributes greatly to decrease the activity, opposite to the trends observed in the literature [27].…”

“…In this regard, the imidazolium skeleton can be transformed into ionic liquids with promisingly potent pharmacological properties [18][19][20][21]. Consequently, monoimidazolium [22][23][24] and bisimidazolium [25][26][27][28] salts have been explored as a new generation of antibacterial agents. In this 2 of 17 context, amino acid-based monoimidazolium salts with good bacterial toxicity have been reported in the literature [29].…”

Antimicrobial Properties and Cytotoxic Effect of Imidazolium Geminis with Tunable Hydrophobicity

“…It should be noted that the compounds of the series n-s-n (Im) show significant activity not only against Gram-positive, but also against Gram-negative bacteria. The latter have an additional outer membrane preventing access to the cell of foreign membranotropic compounds and increasing its resistance to antimicrobial agents, including surfactants [ 22 , 23 ]. However, in relation to Escherichia coli , compounds 10-s-10 (Im) are effective at the level of reference drugs ( Table 1 ).…”

“…Monocationic imidazolium surfactants were synthesized by the interaction of methylimidazole with the corresponding halide alkyl, in analogy with [ 43 , 44 ]. Dicationic imidazolium salts with long-chain alkyl tails and polymethylene bridges (spacer) have been synthesized in two stages in accordance with [ 22 ]: in the first step, imidazole was mono-alkylated, and in the second step, the bridge was introduced ( Scheme 1 ).…”

“…It is worth noting that dicationic surfactants with imidazolium head group have recently been reported: the variation of alkyl tail length and distance between cationic centers [ 17 , 18 , 19 ], introduction of substituents into the spacer fragment [ 20 ], as well as modification of the structure of the imidazolium head group [ 21 ] allows for controlling their aggregation behavior and properties, including antimicrobial activity. Previously, the biological activity of dicationic imidazolium surfactants with decyl and dodecyl tails have been studied in our research group, which showed high antimicrobial effects against a number of test microorganisms, with low cytotoxic activity observed [ 22 ]. In the present work, systematic study of antimicrobial, membranotropic and toxic properties is carried out for the representative series of imidazolium geminis, including lower and higher homologues, as well as for their monocationic analogues, which allows for identifying the relationship between biological activity and structural features of amphiphilic compounds.…”