Choline‐Based Ionic Liquids: Improvement of Antimicrobial Activity

Abstract

Antibiotic resistance is a global public health concern. The choline-based ionic liquids (ILs) have raised particular attention in the design of "greener" ILs and can exert a broad-spectrum of antimicrobial activity. To improve antimicrobial chemotherapy, we herein tested the antimicrobial activity and toxicity of a wide range of choline-based ILs. Two series of compounds were synthesized -dimethylethanolamine monoquaternary ammonium salts (Series A) and -methyl diethanolamine, diethanolamine and triethanolamine monoquaternary ammonium salts (Series B). The antimicrobial screening re-vealed that compounds N-(2-hydroxyethyl)-N,N-dimethyl-1-tetradecanaminium bromide ([N 1,1,14,2(OH) ]Br), N-(2-hydroxyethyl)-N,N-dimethyl-1-hexadecanaminium bromide ([N 1,1,16,2(OH) ]Br) and N-(2-hydroxyethyl)-N,N-dimethyl-1-octadecanaminium bromide ([N 1,1,18,2(OH) ]Br) are potent antimicrobial agents. The presence of a hydroxyethyl group and as mention previously in the literature, the C 14 to C 16 linker in a choline compound improves the antimicrobial activity and lowers the cytotoxic properties of this class of compounds.

Quaternary Ammonium Compounds (QACs) and Ionic Liquids (ILs) as Biocides: From Simple Antiseptics to Tunable Antimicrobials

“…In most cases, there is a direct relation between the length of the alkyl side chain in the cation and the IL antimicrobial activity. ILs with relatively short side chains (ethyl, butyl, hexyl) usually demonstrate weak activity (see Table S1), whereas those with long side chains (dodecyl, tetradecyl, hexadecyl) can be strong inhibitors of some bacterial and fungal species, including biofilmforming and drug-resistant species (see, e.g., entries for [ 2) [92]. Surface-active cholinium ILs with the dodecylbenzenesulfonate anion demonstrated significant activity against Gram-negative and Gram-positive bacteria, fungi, and single-cell algae; these ILs were proposed to be used as coatings for the prevention of biofilm formation on stone surfaces [93].…”

Antimicrobial Activity of Pyrazinamide Coordination Frameworks Synthesized by Mechanochemistry

“…These values were determined by the microdilution method [ 60 , 61 ]. In brief, 100 μL of the Mueller-Hinton liquid culture medium were added to all 96-wells of the microplate, and 100 μL of the testing compounds at a concentration of 1 mg⋅mL −1 in DMSO were added to the first well.…”

Functionalized Cyclopentenones and an Oxime Ether as Antimicrobial Agents

“…In particular, trans‐ diamino‐cyclopentenones (DCPs) and δ‐lactone‐fused cyclopentenones (LCPs) can be prepared respectively from furfural and activated 5‐hydroxymethylfurfural (HMF), both furan derivatives being derived from biomass (Scheme 1B) [13–24] . In line with our interest regarding sustainable production of biologically active compounds, we have also developed choline‐based ionic liquids with antibiotic activity [25] . Herein we report a novel sustainable based cyclopentenone scaffold exhibiting antimicrobial activity against MRSA.…”