scholarly journals Design, Synthesis and Antimicrobial Evaluation of New Norfloxacin-Naphthoquinone Hybrid Molecules

Proceedings ◽  
2019 ◽  
Vol 41 (1) ◽  
pp. 9 ◽  
Author(s):  
Andrea Defant ◽  
Alessandro Vozza ◽  
Ines Mancini
Keyword(s):  
Bacterial Infections ◽  
Antimicrobial Agents ◽  
Biological Activities ◽  
Dna Gyrase ◽  
Structural Features ◽  
Therapeutic Agents ◽  
Topoisomerase Iv ◽  
Design Synthesis ◽  
Biological Targets ◽  
Hybrid Molecules

Although the wide arsenal of drugs available to treat bacterial infections, emerging drug-resistant bacterial pathogens have recently highlighted an urgent need to find new more effective and less toxic therapeutic agents. Fluoroquinolones, including norfloxacin, are antibiotics showing a concentration-dependent bactericidal capacity due to the activity inhibition of DNA-gyrase and topoisomerase IV, which are enzymes essential for bacterial DNA replication. Naphthoquinones are secondary metabolites showing different biological activities, including cytotoxic, antibacterial and antifungal effects. In particular, the efficacy of natural and synthetic 1,4-naphthoquinone derivatives is likely due to their oxidizing/reducing capability, through which they destroy cellular targets as nucleic acids. Hybrid molecules are produced combining structural features of two or more bioactive compounds, in order to obtain new therapeutic agents able, not only to reduce undesirable side effects of the parent drugs, but also to inhibit more biological targets, hopefully with a better therapeutic property than the administration of combined single-target drugs. With the aim to apply this strategy in the study of new potential antimicrobial agents, we have synthesized four hybrid molecules by the reaction of norfloxacin with suitable quinones and their activities have been evaluated against both bacteria and fungi, in comparison with synthetic precursors. The experimental data are supported by docking calculations on S. aureus DNA-gyrase, discussing the interactions involved for each hybrid molecule, in comparison with norfloxacin and the original ligand moxifloxacin.

scholarly journals Delafloxacin, Finafloxacin, and Zabofloxacin: Novel Fluoroquinolones in the Antibiotic Pipeline

Antibiotics ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1506
Author(s):  
Béla Kocsis ◽  
Dániel Gulyás ◽  
Dóra Szabó
Keyword(s):  
Broad Spectrum ◽  
Bacterial Infections ◽  
Chemical Structure ◽  
Antimicrobial Agents ◽  
Treatment Options ◽  
Dna Gyrase ◽  
Daily Practice ◽  
Molecular Surface ◽  
Chronic Obstructive ◽  
Topoisomerase Iv

Novel antimicrobial agents, approved for clinical use in past years, represent potential treatment options for various infections. In this review, we summarize the most important medical and microbiological features of three recently approved fluoroquinolones, namely delafloxacin, finafloxacin, and zabofloxacin. Delafloxacin possesses an anionic chemical structure, and represents broad-spectrum activity, as it targets both bacterial DNA gyrase and topoisomerase IV enzymes of gram-positive and gram-negative bacteria with equal affinity. Its molecular surface is larger than that of other fluoroquinolones, and it has enhanced antibacterial efficacy in acidic environments. Delafloxacin has been approved to treat acute bacterial skin and skin-structure infections, as well as community-acquired bacterial pneumonia. Finafloxacin has a zwitterionic chemical structure, and targets both DNA gyrase and topoisomerase IV enzymes. This enables a broad antibacterial spectrum; however, finafloxacin has so far only been approved in ear-drops to treat bacterial otitis externa. Zabofloxacin is also a broad-spectrum fluoroquinolone agent, and was first approved in South Korea to treat acute bacterial exacerbation of chronic obstructive pulmonary disease. The introduction of these novel fluoroquinolones into daily practice extends the possible indications of antibiotics into different bacterial infections, and provides treatment options in difficult-to-treat infections. However, some reports of delafloxacin resistance have already appeared, thus underlining the importance of the prudent use of antibiotics.

Heterocycle Compounds with Antimicrobial Activity

2020 ◽  
Vol 26 (8) ◽  
pp. 867-904 ◽  
Author(s):  
Maria Fesatidou ◽  
Anthi Petrou ◽  
Geronikaki Athina
Keyword(s):  
Heterocyclic Compounds ◽  
Bacterial Infections ◽  
Scientific Community ◽  
Antimicrobial Agents ◽  
Fungal Infections ◽  
Biological Activities ◽  
Literature Survey ◽  
New Findings ◽  
Wide Range ◽  
Number Of Microorganisms

Background: Bacterial infections are a growing problem worldwide causing morbidity and mortality mainly in developing countries. Moreover, the increased number of microorganisms, developing multiple resistances to known drugs, due to abuse of antibiotics, is another serious problem. This problem becomes more serious for immunocompromised patients and those who are often disposed to opportunistic fungal infections. Objective: The objective of this manuscript is to give an overview of new findings in the field of antimicrobial agents among five-membered heterocyclic compounds. These heterocyclic compounds especially five-membered attracted the interest of the scientific community not only for their occurrence in nature but also due to their wide range of biological activities. Method: To reach our goal, a literature survey that covers the last decade was performed. Results: As a result, recent data on the biological activity of thiazole, thiazolidinone, benzothiazole and thiadiazole derivatives are mentioned. Conclusion: It should be mentioned that despite the progress in the development of new antimicrobial agents, there is still room for new findings. Thus, research still continues.

Coumarin Hybrids: Promising Scaffolds in the Treatment of Breast Cancer

2019 ◽  
Vol 19 (17) ◽  
pp. 1443-1458 ◽  
Author(s):  
Rohit Bhatia ◽  
Ravindra K. Rawal
Keyword(s):  
Breast Cancer ◽  
Lung Cancer ◽  
Therapeutic Agents ◽  
Toxicity Profile ◽  
Biological Targets ◽  
Organ Systems ◽  
Hybrid Molecules ◽  
Cause Of Deaths ◽  
Low Toxicity ◽  
Diverse Mode

: Breast cancer is the most common invasive cancer in women, and the second main cause of deaths in women, after lung cancer. There is continuous advancement in the development of therapeutic agents against breast cancer in recent years and it is still in progress. Development of hybrid molecules by combining different pharmacophores to obtain significant biological activity is an excellent approach. Coupling of coumarin scaffold with other distinct motifs has led to the design of newer compounds against breast cancer. These distinct pharmacophores possess a diverse mode of action as well as selectivity. It has been reported in the literature that coumarin hybrids possess significant potency against breast cancer by binding to various biological targets which are associated with breast cancer. Due to low toxicity profile on various organ systems, coumarin hybrids have nowadays attracted the keen attention of researchers to explore their therapeutic ability against breast cancer. Reported coumarin hybrids include coupling with isoxazole, thiazole, monastrol, chalcone, triazole, sulphonamide, triphenylethylene, benzimidazole, pyran, imidazole, stilbene, oestrogen, phenylsulphonylfuroxan, etc. In the present review, a description of various coumarin hybrid molecules has been presented along with their structural-activity relationships.

Synthesis of novel 2-aminobenzothiazole derivatives as potential antimicrobial agents with dual DNA gyrase/topoisomerase IV inhibition

2020 ◽  
Vol 94 ◽  
pp. 103437 ◽  
Author(s):  
Magda M.F. Ismail ◽  
Hanan Gaber Abdulwahab ◽  
Eman Samir Nossier ◽  
Nagwan Galal El Menofy ◽  
Basma Abdelhameed Abdelkhalek
Keyword(s):  
Antimicrobial Agents ◽  
Dna Gyrase ◽  
Topoisomerase Iv

scholarly journals Synthesis, Antimicrobial Activity and Molecular Docking of Novel Thiourea Derivatives Tagged with Thiadiazole, Imidazole and Triazine Moieties as Potential DNA Gyrase and Topoisomerase IV Inhibitors

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2766 ◽  
Author(s):  
Heba E. Hashem ◽  
Abd El-Galil E. Amr ◽  
Eman S. Nossier ◽  
Elsayed A. Elsayed ◽  
Eman M. Azmy
Keyword(s):  
Antimicrobial Activity ◽  
Molecular Docking ◽  
Antimicrobial Agents ◽  
Biological Activities ◽  
Topoisomerase Iv ◽  
Thiourea Derivatives ◽  
E Coli ◽  
Cytotoxicity Studies ◽  
Ic50 Values

To develop new antimicrobial agents, a series of novel thiourea derivatives incorporated with different moieties 2–13 was designed and synthesized and their biological activities were evaluated. Compounds 7a, 7b and 8 exhibited excellent antimicrobial activity against all Gram-positive and Gram-negative bacteria, and the fungal Aspergillus flavus with minimum inhibitory concentration (MIC) values ranged from 0.95 ± 0.22 to 3.25 ± 1.00 μg/mL. Furthermore, cytotoxicity studies against MCF-7 cells revealed that compounds 7a and 7b were the most potent with IC50 values of 10.17 ± 0.65 and 11.59 ± 0.59 μM, respectively. On the other hand, the tested compounds were less toxic against normal kidney epithelial cell lines (Vero cells). The in vitro enzyme inhibition assay of 8 displayed excellent inhibitory activity against Escherichia coli DNA B gyrase and moderate one against E. coli Topoisomerase IV (IC50 = 0.33 ± 1.25 and 19.72 ± 1.00 µM, respectively) in comparison with novobiocin (IC50 values 0.28 ± 1.45 and 10.65 ± 1.02 µM, respectively). Finally, the molecular docking was done to position compound 8 into the E. coli DNA B and Topoisomerase IV active pockets to explore the probable binding conformation. In summary, compound 8 may serve as a potential dual E. coli DNA B and Topoisomerase IV inhibitor.

scholarly journals Hybrid cis-stilbene Molecules: Novel Anticancer Agents

2019 ◽  
Vol 20 (6) ◽  
pp. 1300 ◽  
Author(s):  
Natalia Piekuś-Słomka ◽  
Renata Mikstacka ◽  
Joanna Ronowicz ◽  
Stanisław Sobiak
Keyword(s):  
Anticancer Agents ◽  
Biological Activities ◽  
Distinct Group ◽  
Design Synthesis ◽  
Drug Candidates ◽  
Structure Activity ◽  
Polymerization Inhibitor ◽  
Hybrid Molecules ◽  
Tubulin Polymerization Inhibitor ◽  
Pharmacologically Active

The growing interest in anticancer hybrids in the last few years has resulted in a great number of reports on hybrid design, synthesis and bioevaluation. Many novel multi-target-directed drug candidates were synthesized, and their biological activities were evaluated. For the design of anticancer hybrid compounds, the molecules of stilbenes, aromatic quinones, and heterocycles (benzimidazole, imidazole, pyrimidine, pyridine, pyrazole, quinoline, quinazoline) were applied. A distinct group of hybrids comprises the molecules built with natural compounds: Resveratrol, curcumin, coumarin, and oleanolic acid. In this review, we present the studies on bioactive hybrid molecules of a well-known tubulin polymerization inhibitor, combretastatin A-4 and its analogs with other pharmacologically active entities. The mechanism of anticancer activity of selected hybrids is discussed considering the structure-activity relationship.

Corrigendum to “Synthesis of novel 2-aminobenzothiazole derivatives as potential antimicrobial agents with dual DNA gyrase/topoisomerase IV inhibition” [Bioorg. Chem. 94 (2020) 103437]

2020 ◽  
Vol 98 ◽  
pp. 103716
Author(s):  
Magda M.F. Ismail ◽  
Hanan Gaber Abdulwahab ◽  
Eman Samir Nossier ◽  
Nagwan Galal El Menofy ◽  
Basma Abdelhameed Abdelkhalek
Keyword(s):  
Antimicrobial Agents ◽  
Dna Gyrase ◽  
Topoisomerase Iv

scholarly journals In Vitro Evaluation of CBR-2092, a Novel Rifamycin-Quinolone Hybrid Antibiotic: Studies of the Mode of Action in Staphylococcus aureus

2008 ◽  
Vol 52 (7) ◽  
pp. 2313-2323 ◽  
Author(s):  
Gregory T. Robertson ◽  
Eric J. Bonventre ◽  
Timothy B. Doyle ◽  
Qun Du ◽  
Leonard Duncan ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Rna Polymerase ◽  
Mode Of Action ◽  
Bacterial Infections ◽  
Dna Gyrase ◽  
Topoisomerase Iv ◽  
Dna Topoisomerase ◽  
Resistant Variant ◽  
Proven Efficacy

ABSTRACT Rifamycins have proven efficacy in the treatment of persistent bacterial infections. However, the frequency with which bacteria develop resistance to rifamycin agents restricts their clinical use to antibiotic combination regimens. In a program directed toward the synthesis of rifamycins with a lower propensity to elicit resistance development, a series of compounds were prepared that covalently combine rifamycin and quinolone pharmacophores to form stable hybrid antibacterial agents. We describe mode-of-action studies with Staphylococcus aureus of CBR-2092, a novel hybrid that combines the rifamycin SV and 4H-4-oxo-quinolizine pharmacophores. In biochemical studies, CBR-2092 exhibited rifampin-like potency as an inhibitor of RNA polymerase, was an equipotent (balanced) inhibitor of DNA gyrase and DNA topoisomerase IV, and retained activity against a prevalent quinolone-resistant variant. Macromolecular biosynthesis studies confirmed that CBR-2092 has rifampin-like effects on RNA synthesis in rifampin-susceptible strains and quinolone-like effects on DNA synthesis in rifampin-resistant strains. Studies of mutant strains that exhibited reduced susceptibility to CBR-2092 further substantiated RNA polymerase as the primary cellular target of CBR-2092, with DNA gyrase and DNA topoisomerase IV being secondary and tertiary targets, respectively, in strains exhibiting preexisting rifampin resistance. In contrast to quinolone comparator agents, no strains with altered susceptibility to CBR-2092 were found to exhibit changes consistent with altered efflux properties. The combined data indicate that CBR-2092 may have potential utility in monotherapy for the treatment of persistent S. aureus infections.

scholarly journals An Overview of Bioactive 1,3-Oxazole-Containing Alkaloids from Marine Organisms

2021 ◽  
Vol 14 (12) ◽  
pp. 1274
Author(s):  
Jinyun Chen ◽  
Sunyan Lv ◽  
Jia Liu ◽  
Yanlei Yu ◽  
Hong Wang ◽  
...  
Keyword(s):  
Nitrogen Atom ◽  
Chemical Synthesis ◽  
Biological Activities ◽  
Structural Features ◽  
Biological Properties ◽  
Therapeutic Agents ◽  
Marine Organisms ◽  
Chemical Structures ◽  
First Time ◽  
Oxazole Derivatives

1,3-Oxazole chemicals are a unique class of five-membered monocyclic heteroarenes, containing a nitrogen atom and an oxygen. These alkaloids have attracted extensive attention from medicinal chemists and pharmacologists owing to their diverse arrays of chemical structures and biological activities, and a series of 1,3-oxazole derivatives has been developed into therapeutic agents (e.g., almoxatone, befloxatone, cabotegravir, delpazolid, fenpipalone, haloxazolam, inavolisib). A growing amount of evidence indicates that marine organisms are one of important sources of 1,3-oxazole-containing alkaloids. To improve our knowledge regarding these marine-derived substances, as many as 285 compounds are summarized in this review, which, for the first time, highlights their sources, structural features and biological properties, as well as their biosynthesis and chemical synthesis. Perspective for the future discovery of new 1,3-oxazole compounds from marine organisms is also provided.

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