Title:Enhanced Antibacterial Activity of Endo-nortropine Substituted (C-7) Fluoroquinolones Against V. cholerae, S. aureus and B. subtilis
Volume: 15
Issue: 8
Author(s): Ramkrushna Ashok Salunke, Chandni Sidhu, Ashok Kumar, Anil Kumar Pinnaka, Baldev Raj Bansal and Manmohan Chhibber*
Affiliation:
- School of Chemistry and Biochemistry, Thapar University, Patiala-147004, (Punjab),India
Keywords:
Levofloxacin, Tropine alkaloids, DNA gyrase, Piperazine, MRSA, VRSA.
Abstract: Introduction: Bacterial infections account for maximum deaths worldwide than for any
other single cause.
Methods: Here in, we report a convenient synthesis of new fluoroquinolone molecules substituted
with endo- nortropine and its derivatives at C-7position. All the synthesized molecules, when
screened for their antibacterial activity by agar diffusion method against Vibrio cholerae, Bacillus
subtilis, Staphylococcus aureus and Escherichia coli were found to be active against the first three
strains. The shortlisted compounds in the series, RG and RO, were further evaluated to determine
their MIC values by micro-dilution broth assay.
Result & Conclusion: Compound RG was ten times more effective in case of S. aureus (15.0 nM),
two times in case of V. cholerae (3.7 nM) and the same as that of standard drug Levofloxacin in case of
Bacillus subtilis (7.8 nM). Compound RO also displayed an impressive MIC value (62.5 nM) in case
of S. aureus as compared to control (125 nM). The results have been supported by in-silico docking
studies, where increased hydrogen bonding interactions in case of RG as compared to standard drug
levofloxacin with DNA gyrase (2XCT) of S. aureus resulted in decreased energy of the former.