Related Experiment Video
Updated: Jan 2, 2026
05:59
Author Spotlight: Advancing Antimicrobial Resistance Research with Innovative Approaches and Synthetic Compounds
Published on: September 27, 2024
2.5K
Antimicrobial Activity of Quinoline-Based Hydroxyimidazolium Hybrids
Daniel Insuasty1, Oscar Vidal1, Anthony Bernal1
1Departamento de Química y Biología, Universidad del Norte, Km 5 vía Puerto Colombia, Barranquilla 081007, Colombia.
Antibiotics (Basel, Switzerland)
|December 5, 2019
Summary
New quinoline-based hydroxyimidazolium hybrids show potent antimicrobial activity. Hybrid 7b is particularly effective against Staphylococcus aureus and Mycobacterium tuberculosis, demonstrating high selectivity and potential for further research.
Area of Science:
- Medicinal Chemistry
- Antimicrobial Drug Discovery
- Organic Synthesis
Background:
- Fungal and bacterial infections pose significant global health challenges.
- Development of novel antimicrobial agents is crucial to combat rising resistance.
- Quinoline and imidazolium scaffolds are known for their biological activities.
Purpose of the Study:
- To synthesize and evaluate novel quinoline-based hydroxyimidazolium hybrids for antimicrobial properties.
- To identify potent compounds against clinically relevant pathogens, including fungi, bacteria, and mycobacteria.
- To assess the selectivity of promising compounds against mammalian cells.
Main Methods:
- Synthesis of eight quinoline-based hydroxyimidazolium hybrids (compounds 7a-h).
- In vitro evaluation of antimicrobial activity using minimum inhibitory concentration (MIC) assays.
- Testing against a panel of fungal pathogens (Cryptococcus neoformans, Candida spp., Aspergillus spp.) and bacterial pathogens (Gram-negative bacteria, Klebsiella pneumoniae, Staphylococcus aureus, Mycobacterium tuberculosis H37Rv).
- Selectivity testing against mammalian cells.
Main Results:
- Compounds 7c-d exhibited strong antifungal activity against Cryptococcus neoformans (MIC = 15.6 µg/mL).
- Hybrid 7b demonstrated potent activity against Staphylococcus aureus (MIC = 2 µg/mL) and Mycobacterium tuberculosis H37Rv (MIC = 10 µg/mL).
- Hybrid 7b showed high selectivity (SI >20) for killing S. aureus and M. tuberculosis H37Rv compared to mammalian cells.
Conclusions:
- Quinoline-based hydroxyimidazolium hybrids represent a promising class of antimicrobial agents.
- Hybrid 7b is identified as a hit molecule with potent and selective activity against S. aureus and M. tuberculosis.
- Further studies on hybrid 7b are warranted to explore its mechanism of action and optimize its chemical space.
Related Concept Videos
01:11Aryldiazonium Salts to Azo Dyes: Diazo Coupling
3.5K
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para...
3.5K
01:25Basicity of Heterocyclic Aromatic Amines
6.8K
Heterocyclic amines, where the N atom is a part of an alicyclic system, are similar in basicity to alkylamines. Interestingly, the heterocyclic amine having a nitrogen atom as part of an aromatic ring has much less basicity than its corresponding alicyclic counterpart. For this reason, as presented in Figure 1, piperidine (pKb = 2.8) is significantly more basic than pyridine (pKb = 8.8).
6.8K
01:28Antimicrobial Effectiveness
861
The effectiveness of antimicrobial agents depends on various factors influencing their ability to eliminate microbial populations. Larger microbial populations require more time for complete eradication, emphasizing the importance of population size analysis when evaluating antimicrobial efficacy.Microbial resistance to antimicrobial agents varies significantly. Highly resilient microorganisms include endospores, gram-negative bacteria, and non-enveloped viruses, while prions are exceptionally...
861
01:27Combined Effects of Drugs: Synergism
6.7K
Synergism is a useful mechanism where combining two or more drugs is more effective than each constituent used alone. Such combinations are also called supra-additive interactions. The drugs collectively enhance the final therapeutic effect by acting on different targets. Another advantage is that the low dose of each constituent drug is sufficient to achieve the desired effect. This helps reduce the duration of therapy and lower the adverse effects of these drugs.
Such synergistic combinations...
Such synergistic combinations...
6.7K
01:28Gene Regulation in Microbial Communities: Quorum Sensing
437
Quorum sensing is a mechanism of bacterial communication that enables coordinated gene expression in response to changes in population density. This facilitates collective behaviors that enhance survival, resource acquisition, and ecological adaptation. This process relies on small signaling molecules called autoinducers that accumulate as bacterial populations grow. When a critical threshold concentration of autoinducers is reached, bacterial cells collectively modify gene expression,...
437
01:19Diazonium Group Substitution: –OH and –H
3.2K
Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
3.2K