Indium(III) 8-hydroxyquinolinates: Activity and selectivity towards multi-drug resistant strains of Klebsiella pneumoniae
Year: 2025
Type: article
Abstract: A series of dimethyl indium(III) 8-hydroxyquinolinates; [InMe 2 (Q")] ( 1 ), [InMe 2 (Q'Cl)] ( 2 ), [InMe 2 (QCl 2 )] ( 3 ), [InMe 2 (QBr 2 )] ( 4 ), [InMe 2 (QI 2 )] ( 5 ), [InMe 2 (QICl)] ( 6 ), and a series of indium(III) tris (8-hydroxyquinolinates); [In(Q") 3 ]•H 2 O ( 7 ), [In(QCl 2 ) 3 ] ( 8 ), [In(QBr 2 ) 3 ] ( 9 ), [In(QI 2 ) 3 ] ( 10 ), and [In(QICl) 3 ] ( 11 ), (where Q"- H = C 9 H 7 NO; Q'Cl- H = C 9 H 6 NOCl, QCl 2 - H = C 9 H 5 NOCl 2 ; QBr 2 - H = C 9 H 5 NOBr 2 ; QI 2 - H = C 9 H 5 NOI 2 ; and QICl- H = C 9 H 5 NOICl) were synthesised, characterised, and evaluated for their antibacterial activity against Gram-positive bacteria (vancomycin-resistant E. faecalis , S. aureus , methicillin-resistant S. aureus ), Gram-negative bacteria ( K. pneumoniae , A. baumannii , P. aeruginosa , and E. coli ) and mammalian cell inhibition of L929 fibroblasts. Single crystal X-ray diffraction data of 2–4 indicates the dimethylindium complexes are dimeric in the solid-state through ‘In 2 O 2 ’ bridging. Complexes 1–6 exhibit significant activity and selectivity against three multi-drug resistant strains of K. pneumoniae , with MIC (minimum inhibitory concentration) values as low as 49 nM and selectivity indices as high as 159 against carbapenem-resistant strain RH201207. The antibacterial activity and selectivity against K. pneumoniae is generally enhanced upon complexation of the 8-hydroxyquinolinate ligands to indium(III).
Institution: Monash University
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,220
OpenAlex ID: W4413118512