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Updated: Jul 6, 2026
11:51
Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
N-Substituted piperazinyl quinolones as potential cytotoxic agents: structure-activity relationships study
Alireza Foroumadi1, Saeed Emami, Saeed Rajabalian
1Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran 14174, Iran.
Summary
Researchers explored new piperazinyl quinolone compounds for anticancer potential. Introducing a 2-(5-chlorothiophen-2-yl)ethyl group transformed antibacterial quinolones into potent cytotoxic agents against cancer cells.
Area of Science:
- Medicinal Chemistry
- Drug Discovery
- Oncology
Background:
- The piperazinyl quinolone scaffold is a known pharmacophore with antibacterial properties.
- A continuing search for novel anticancer agents is crucial in oncology.
- Modifying existing drug scaffolds can lead to new therapeutic applications.
Purpose of the Study:
- To synthesize and evaluate the cytotoxicity of novel N-substituted piperazinyl quinolones.
- To investigate the structure-activity relationships of these compounds against cancer cell lines.
- To explore the potential of piperazinyl quinolones as anticancer candidates.
Main Methods:
- Synthesis of 12 new N-[2-(5-chlorothiophen-2-yl)-2-oxoethyl] and N-[2-(5-chlorothiophen-2-yl)-2-oxyiminoethyl] piperazinyl quinolones.
- Cytotoxicity evaluation using the MTT colorimetric assay against six human cancer cell lines.
- Structure-activity relationship analysis based on modifications to the ethyl spacer and oxime moiety.
Main Results:
- Compounds 4-12, featuring the 2-(5-chlorothiophen-2-yl)ethyl moiety with an oxime group, exhibited significant cytotoxic activity.
- Minor modifications to the functionality on the ethyl spacer resulted in relatively small changes in activity.
- The introduction of the 2-(5-chlorothiophen-2-yl)ethyl residue positively modulated cytotoxic activity.
Conclusions:
- The 2-(5-chlorothiophen-2-yl)ethyl moiety is a key structural feature for conferring cytotoxic activity in this series.
- Piperazinyl quinolones can be repurposed from antibacterials to potent cytotoxic agents by structural modification.
- These findings highlight a promising new direction for developing piperazinyl quinolone-based anticancer therapeutics.
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