title: N, N'-Olefin functionalized bis-imidazolium gold(I) salt is an efficient candidate to control keratitis-associated eye infection.
abstract: Keratitis treatment has become more complicated due to the emergence of bacterial or fungal pathogens with enhanced antibiotic resistance. The pharmaceutical applications of N-heterocyclic carbene complexes have received remarkable attention due to their antimicrobial properties. In this paper, the new precursor, 3,3'-(p-phenylenedimethylene) bis{1-(2- methyl-allyl)imidazolium} bromide (1a) and its analogous PF6 salt (1b) were synthesized. Furthermore, silver(I) and gold(I) -N-heterocyclic carbene (NHC) complexes [Ag2LBr2/Au2LBr2; 2a/3a], [(Ag2L2)(PF6)2/(Au2L2)(PF6)2; 2b/3b] were developed from their corresponding ligands. All compounds were screened for their antimicrobial activities against multiple keratitis-associated human eye pathogens, including bacteria and fungi. Complexes 2a and 3a showed highest activity, and the effectiveness of 3a was also studied, focusing eradication of pathogen biofilm. Furthermore, the structures of 1a, 2a and 3b were determined using single crystal X-ray analysis, 2b and 3a were optimized theoretically. The mechanism of action of 3a was evaluated by scanning electron microscopy and docking experiments, suggesting that its target is the cell membrane. In summary, 3a may be helpful in developing antimicrobial therapies in patients suffering from keratitis-associated eye infections caused by multidrug-resistant pathogens.
authors.affiliation: School of Applied Sciences, Haldia Institute of Technology, Haldia, West Bengal, India.
authors.forename: Tapastaru
authors.initials: T
authors.lastname: Samanta
authors.forename: Gourisankar
authors.initials: G
authors.lastname: Roymahapatra
authors.forename: William F
authors.initials: WF
authors.lastname: Porto
authors.forename: Saikat
authors.initials: S
authors.lastname: Seth
authors.forename: Sudipta
authors.initials: S
authors.lastname: Ghorai
authors.forename: Suman
authors.initials: S
authors.lastname: Saha
authors.forename: Jayangshu
authors.initials: J
authors.lastname: Sengupta
authors.forename: Octávio L
authors.initials: OL
authors.lastname: Franco
authors.forename: Joydev
authors.initials: J
authors.lastname: Dinda
authors.forename: Santi M
authors.initials: SM
authors.lastname: Mandal
mesh_terms: D000475:Alkenes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D000890:Anti-Infective Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D018441:Biofilms; D045744:Cell Line, Tumor; D003261:Contact Lenses / Q000382:microbiology; D003262:Contact Lenses, Extended-Wear; D015817:Eye Infections / Q000188:drug therapy* / Q000209:etiology / Q000382:microbiology; D006046:Gold / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D007093:Imidazoles / Q000737:chemistry / Q000494:pharmacology*; D007634:Keratitis / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology; D051379:Mice
chemical_list: D000475:Alkenes; D000890:Anti-Infective Agents; D007093:Imidazoles; D006046:Gold; C029899:imidazole
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