Double Alkynylation of Quinoline-5,8-diones and their <i>In-silico</i> and Antimicrobial Studies

Abstract

A double alkynylation of quinoline-5,8-dione to furnished bis-alkynylquinoline-5,8-dione in good yields and their in silico and antimicrobial studies is described. This was achieved by cross-coupling of 6,7dibromoquinoline-5,8-dione with various terminal alkynes in the presence of bis(triphenylphosphine) palladium(II) chloride as a pre-catalyst and tetrabutyl ammonium fluoride trihydrate. The structures of the synthesised compounds were confirmed by UV/Visible, Fourier Transform-Infrared and 1 H and 13 C-NMR spectral data. The synthesised compounds exhibited good activity against Escherichia Coli 1, Escherichia Coli 12, Klebsiella Pneumonia, Pseudomonas aeroginosa and Staphylococcus aureus compare to the gentamycin and ampicillin. Molecular docking simulation study of the binding interactions of compounds with receptors disclosed significant binding affinity for P. aeruginosa LpxC than the E. coli glutaredoxin.

5,8-Quinolinedione Scaffold as a Promising Moiety of Bioactive Agents

“…The 5,8-quinolinedione moiety contains a double bond between the C-6 and C-7 carbon atom, which enables the enediyne fragment to be obtained by a reaction with terminal alkynes. Ezeokonkwa et al described the synthesis of mono- ( 94 – 96 ) (Figure 16) and disubstituent ( 97 – 99 ) (Figure 16) hybrids of 5,8-quinolinedione with terminal alkynes and their antibacterial activity against E. coli 12 , K. pneumonia , S. aureus , and P. aeruiginosa [93,94].…”