RESUMEN
The structural optimization of B14, an antibacterial agent we previously obtained, has led to the discovery of a new class of CH2-linked quinolone-aminopyrimidine hybrids with potent anti-MRSA activities. Surprisingly, the hybrids lacking a C-6 fluoro atom at the quinolone nucleus showed equal or even stronger anti-MRSA activities than their corresponding 6-fluoro counterparts, despite the well-established structure-activity relationships (SARs) indicating that the 6-fluoro substituent enhances the antibacterial activity in conventional fluoroquinolone antibiotics. Moreover, these new hybrids, albeit structurally related to conventional fluoroquinolones, showed no cross-resistance with fluoroquinolone drugs. The most active compound, 15m, exhibited excellent activities with a MIC value of 0.39 µg/mL against both fluoroquinolone-sensitive strain USA500 and -resistant MRSA isolate Mu50. Further resistance development studies indicated MRSA is unlikely to acquire resistance against 15m. Moreover, 15m displayed favorable in vivo half-life and safety profiles. These findings suggest a rationale for further evolution of quinolone antibiotics with a high barrier to resistance.
Asunto(s)
Antibacterianos , Fluoroquinolonas , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Pirimidinas , Quinolonas , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Relación Estructura-Actividad , Pirimidinas/farmacología , Pirimidinas/química , Pirimidinas/síntesis química , Fluoroquinolonas/farmacología , Fluoroquinolonas/química , Fluoroquinolonas/síntesis química , Quinolonas/farmacología , Quinolonas/química , Quinolonas/síntesis química , Estructura Molecular , Farmacorresistencia Bacteriana/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Animales , HumanosRESUMEN
Bacterial resistance threatens the utility of currently available antibiotics. Rifampicin, a cornerstone in the treatment of persistent Gram-positive infections, is prone to the development of resistance resulting from single point mutations in the antibiotic's target, RNA polymerase. One strategy to circumvent resistance is the use of 'hybrid' antibiotics consisting of two covalently linked antibiotic entities. These compounds generally have two distinct cellular targets, reducing the probability of resistance development and potentially providing simplified pharmacological properties compared to combination therapies using the individual antibiotics. Here we evaluate a series of semi-synthetic hybrid antibiotics formed by linking kanglemycin A (Kang A), a rifampicin analog, and a collection of fluoroquinolones. Kang A is a natural product antibiotic which contains a novel dimethyl succinic acid moiety that offers a new attachment point for the synthesis of hybrid antibiotics. We compare the activity of the Kang A hybrids generated via the acid attachment point to a series of hybrids linked at the compound's naphthoquinone ring system. Several hybrids exhibit activity against bacteria resistant to Kang A via the action of the partnered antibiotic, suggesting that the Kang scaffold may provide new avenues for generating antibiotics effective against drug-resistant infections.
Asunto(s)
Antibacterianos/farmacología , Fluoroquinolonas/farmacología , Rifamicinas/farmacología , Antibacterianos/síntesis química , Antibacterianos/toxicidad , Farmacorresistencia Bacteriana/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Fluoroquinolonas/síntesis química , Fluoroquinolonas/toxicidad , Células HEK293 , Humanos , Pruebas de Sensibilidad Microbiana , Rifamicinas/síntesis química , Rifamicinas/toxicidad , Staphylococcus aureus/efectos de los fármacosRESUMEN
Levonadifloxacin is a parenteral anti-MRSA benzoquinolizine antibacterial drug recently launched as, EMROK in India to treat acute bacterial skin and skin structure infections (ABSSSI) in hospitalized patients. As a step down therapy an oral form of levonadifloxacin with comparable PK/PD was needed because the levonadifloxacin exhibits very poor oral absorption. To improve the drugability in terms of oral absorption a pro-drug approach was evaluated. Structurally levonadifloxacin provides two sites amenable for ester or amide formation, a carboxyl function of benzoquinolizine pharmacophore and hydroxyl group on piperidine side chain. Several aliphatic, aromatic and amino acid esters of C-2 carboxylic acid, C-4-hydroxyl piperidine and double esters at both C-2, C-4 positions were synthesized. The cleavage of prodrugs was studied in vitro as well as in animal models to access their suitability as prodrug function. Among C-2 carboxylic ester prodrugs, daloxate (WCK 2320) showed highest cleavage in serum as well as in liver enzyme; however its stability in aqueous solution was unfavorable. In contrast, most of the esters at the hydroxyl group like propionyl ester (WCK 2305) and amino acid esters such as l-alanine (WCK 2349), l-valine (WCK 2630) were cleaved readily releasing active drug. Thus, indicating C-4-hydroxyl piperidine was amenable site for enzymatic cleavage over esters of C-2 carboxylic acid. Additionally, amino acid esters provided an opportunity to make salt, facilitating improved aqueous solubility. Methanesulfonate salt of l-alanine ester of levonadifloxacin (WCK 2349) was successfully developed and launched as oral prodrug alalevonadifloxacin (EMROK-O).
Asunto(s)
Alanina/farmacología , Antibacterianos/farmacología , Diseño de Fármacos , Fluoroquinolonas/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Profármacos/farmacología , Infecciones Estafilocócicas/tratamiento farmacológico , Alanina/síntesis química , Alanina/química , Antibacterianos/síntesis química , Antibacterianos/química , Relación Dosis-Respuesta a Droga , Fluoroquinolonas/síntesis química , Fluoroquinolonas/química , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Profármacos/síntesis química , Profármacos/química , Relación Estructura-ActividadRESUMEN
As vosaroxin as a fluoroquinolone (FQ) had anticancer effectiveness; this study aimed to screen new lipophilic FQs for their dual antimicrobial-antiproliferative activities. Using sulforhodamine B assay; 36 lipophilic FQs have been screened for antimicrobial propensities against S. aureus, E. coli, and C. albicans vs. the respective references ciprofloxacin and fluconazole. They were also explored against a battery of cancer cell lines. Normal periodontal ligament fibroblasts (PDL) were tested for safety examination in comparison to the cisplatin. Reduced FQ compound 4g (R-2, 4-DMeOACA) highly scored nanomolar potency with MIC value of 0.004 µM against gram-positive bacteria. The highest activity of the 36 lipophilic FQs was noted on Leukaemia K562, cervical HELA and pancreatic PANC-1 cancer cell lines with respective IC50 value of 0.005 µM for compound R-4-BuACA (4e), 0.40 µM with CHxCA (7a) and 0.11 µM for R-4-HxACA (4f). Tested FQs exhibited cytotoxicity in A549 lung cancer, MCF-7 and T47D breast cancer cell lines. The reduced 4e and 4f compounds have shown nanomolar inhibition against K562 (as of 4e), PANC-1 and MCF-7 (as of 4f) with IC50 values of 0.005, 0.11 and 0.30 µM, respectively. Succinctly FQs' dual gram-positive antibacterial-antineoplastic capacities expand on of drug design scaffolds in lead generation.
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Asunto(s)
Antiinfecciosos/farmacología , Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Fluoroquinolonas/farmacología , Antiinfecciosos/síntesis química , Antineoplásicos/síntesis química , Candida albicans/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Diseño de Fármacos , Escherichia coli/efectos de los fármacos , Fluoroquinolonas/síntesis química , Humanos , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacosRESUMEN
A new series of nitric oxide-donating fluoroquinolone/oximes was prepared in this study. The nitric oxide release from the prepared compounds was measured using a modified Griess colorimetric method. The antitubercular evaluation of the synthesized compounds indicated that ketone derivatives 2b and 2e and oximes 3b and 3d exhibited somewhat higher activity than their respective parent fluoroquinolones. Mycobacterial DNA cleavage studies and molecular modeling of Mycobacterium tuberculosis DNA gyrase were pursued to explain the observed bioactivity. More important, antibacterial evaluation showed that oximes 3c-e are highly potent against Klebsiella pneumoniae, with minimum inhibitory concentration (MIC) values of 0.06, 0.08, and 0.034 µM, respectively, whereas ketone 2c and oxime 4c are more active against Staphylococcus aureus than ciprofloxacin (MIC values: 0.7, 0.38, and 1.6 µM, respectively). Notably, the antipseudomonal activities of compounds 2a and 4c were much higher than those of their respective parent fluoroquinolones.
Asunto(s)
Antibacterianos/farmacología , Fluoroquinolonas/farmacología , Donantes de Óxido Nítrico/farmacología , Oximas/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Antituberculosos/síntesis química , Antituberculosos/química , Antituberculosos/farmacología , Bacterias/efectos de los fármacos , Ciprofloxacina/farmacología , Fluoroquinolonas/síntesis química , Fluoroquinolonas/química , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Óxido Nítrico/metabolismo , Donantes de Óxido Nítrico/síntesis química , Donantes de Óxido Nítrico/química , Oximas/síntesis química , Oximas/química , Relación Estructura-ActividadRESUMEN
BACKGROUND: Bacterial infections are considered as one of the major global health threats, so it is very essential to design and develop new antibacterial agents to overcome the drawbacks of existing antibacterial agents. METHODS: The aim of this work is to synthesize a series of new fluoroquinolone-3-carboxamide amino acid conjugates by molecular hybridization. We utilized benzotriazole chemistry to synthesize the desired hybrid conjugates. RESULTS: All the conjugates were synthesized in good yields, characterized, evaluated for their antibacterial activity. The compounds were screened for their antibacterial activity using methods adapted from the Clinical and Laboratory Standards Institute. Synthesized conjugates were tested for activity against medically relevant pathogens; Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27856) Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 19433). CONCLUSION: The observed antibacterial experimental data indicates the selectivity of our synthesized conjugates against E.Coli. The protecting group on amino acids decreases the antibacterial activity. The synthesized conjugates are non-toxic to the normal cell lines. The experimental data were supported by computational studies.
Asunto(s)
Aminoácidos/química , Antibacterianos/síntesis química , Antibacterianos/farmacología , Fluoroquinolonas/síntesis química , Fluoroquinolonas/farmacología , Modelos Moleculares , Antibacterianos/química , Línea Celular , Técnicas de Química Sintética , Fluoroquinolonas/química , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Relación Estructura-ActividadRESUMEN
BACKGROUND: Increasing bacterial resistance to quinolones is concerning. Hence, the development of novel quinolones by chemical modifications to overcome quinolone resistance is an attractive perspective in this context. OBJECTIVE: In this study, it is aimed to design and synthesize a novel series of functionalized fluoroquinolones using ciprofloxacin and sarafloxacin cores by hybridization of quinazolinone derivatives. This objective was tested by a comprehensive set of in vitro antibacterial assays in addition to SAR (structure-activity relationship) characterisation studies. METHODS: A nucleophilic reaction of ciprofloxacin and sarafloxacin with 2-(chloromethyl)quinazolin-4(3H)-one in the presence of NaHCO3 in dimethylformamide (DMF) was performed to obtain the desired compounds 5a-j. Novel compounds were characterised by 1H, 13C- NMR and IR spectroscopy, MS and elemental analysis. In silico pharmacokinetics prediction assays and molecular docking studies were performed to explore the binding characteristics and interactions. Antibacterial activities of the novel compounds were evaluated by Broth microdilution, well diffusion and disc diffusion assays against three gram-positive (Methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus and Enterococcus faecalis) and three gram-negative bacteria (Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli). RESULTS: The compounds exhibited moderate to good activities against gram-positive bacteria and weak to moderate activities against gram-negative bacteria. Amongst all ciprofloxacin-derivatives, compound 5d was the most potent agent with high antibacterial activity against gram-positive bacteria, including MRSA and S. aureus ((minimum inhibitory concentration (MIC) = 16 nM for both), that is 60 times more potent than ciprofloxacin as parent drug. Compound 5i from sarafloxacin-derivatives was the most potent compound against MRSA and S. aureus (MIC = 0.125 µM). Well diffusion and disk diffusion assay results demonstrated confirmatory outcomes for the quantitative broth microdilution assay. Molecular docking study results were in accordance with the results of antibacterial activity assays. CONCLUSION: The results of the current study demonstrated that the novel ciprofloxacin and sarafloxacin derivatives synthesized here have promising antibacterial activities. Particularly, compounds 5d and 5i have potential for wider antibacterial applications following further analysis.
Asunto(s)
Antibacterianos/síntesis química , Fluoroquinolonas/síntesis química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Quinazolinonas/química , Antibacterianos/química , Antibacterianos/farmacología , Ciprofloxacina/análogos & derivados , Ciprofloxacina/química , Fluoroquinolonas/química , Fluoroquinolonas/farmacología , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-ActividadAsunto(s)
Antineoplásicos/uso terapéutico , Desarrollo de Medicamentos , Fluoroquinolonas/uso terapéutico , Compuestos Heterocíclicos/uso terapéutico , Alcaloides Indólicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Antineoplásicos/síntesis química , Antineoplásicos/química , Fluoroquinolonas/síntesis química , Fluoroquinolonas/química , Compuestos Heterocíclicos/síntesis química , Compuestos Heterocíclicos/química , Humanos , Alcaloides Indólicos/síntesis química , Alcaloides Indólicos/químicaRESUMEN
Despite the fact that the introduction of a fluorine atom at the C-6 position has resulted in the evolution of fluoroquinolones, fluoroquinolone-induced cardiac toxicity has drawn considerable attention. In this context, desfluoroquinolone-based hybrids with involvement of C-7 aminopyrimidine functional group were designed and synthesized. The biological results showed majority of these hybrids still demonstrated potent anti-MRSA activity with MIC values between 0.38 and 1.5 µg/mL, despite the lack of the typical C-6 fluorine atom. Particularly, the most active B14 exhibited activities at submicromolar concentrations against a panel of MRSA strains including vancomycin-intermediate strains, levofloxacin-resistant isolates, and linezolid-resistant isolates, etc. As expected, it also displayed highly selective toxicity toward bacterial cells and low hERG inhibition. Further resistance development study indicated MRSA is unlikely to acquire resistance against B14. The docking study revealed that two hydrogen bonds were formed between the C-7 substituent and the surrounding DNA bases, which might contribute to overcome resistance by reducing the dependence on the magnesium-water bridge interactions with topoisomerase IV. These results indicate a promising strategy for developing new antibiotic quinolones to combat multidrug resistance and cardiotoxicity.
Asunto(s)
Fluoroquinolonas/síntesis química , Fluoroquinolonas/uso terapéutico , Pirimidinas/síntesis química , Pirimidinas/uso terapéutico , Fluoroquinolonas/farmacología , Humanos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Estructura Molecular , Pirimidinas/farmacología , Relación Estructura-ActividadRESUMEN
Delafloxacin, a fourth-generation anionic fluoroquinolone (FQ) was approved in 2019 for community acquired bacterial pneumonia (CARP). It has broad spectrum activity and an improved class-related toxicity profile. However, it has recently failed a Phase 3 clinical trial for treatment of N. gonorrhoeae infections due to the lack of sufficient efficacy at the dose administered. Inspired by the microbiological and safety profile of delafloxacin, we have developed and profiled the first reported delafloxacin carbon analogue whereby a Nitrogen-for-Carbon swap has been successfully carried out at the C7 position. Not only have we shown that compounds with this modification maintain activity against N. gonorrhoeae (plus other gram-positive and gram-negative bacteria) but they also demonstrate a differentiated physicochemical profile. A zwitterionic derivative of delafloxacin was also profiled and demonstrated a superior microbiological profile against gram-negative strains, whilst maintaining favorable selected ADMET properties.
Asunto(s)
Antibacterianos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Carbono/farmacología , Fluoroquinolonas/farmacología , Neisseria gonorrhoeae/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Carbono/química , Relación Dosis-Respuesta a Droga , Fluoroquinolonas/síntesis química , Fluoroquinolonas/química , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-ActividadRESUMEN
Herein we report the design, synthesis and biological evaluation of structurally modified ciprofloxacin, norfloxacin and moxifloxacin standard drugs, featuring amide functional groups at C-3 of the fluoroquinolone scaffold. In vitro antimicrobial testing against various Gram-positive bacteria, Gram-negative bacteria and fungi revealed potential antibacterial and antifungal activity. Hybrid compounds 9 (MIC 0.2668 ± 0.0001 mM), 10 (MIC 0.1358 ± 00025 mM) and 13 (MIC 0.0898 ± 0.0014 mM) had potential antimicrobial activity against a fluoroquinolone-resistant Escherichia coli clinical isolate, compared to ciprofloxacin (MIC 0.5098 ± 0.0024 mM) and norfloxacin (MIC 0.2937 ± 0.0021 mM) standard drugs. Interestingly, compound 10 also exerted potential antifungal activity against Candida albicans (MIC 0.0056 ± 0.0014 mM) and Penicillium chrysogenum (MIC 0.0453 ± 0.0156 mM). Novel derivatives and standard fluoroquinolone drugs exhibited near-identical cytotoxicity levels against L6 muscle cell-line, when measured using the MTT assay.
Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Diseño de Fármacos , Fluoroquinolonas/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Antifúngicos/síntesis química , Antifúngicos/química , Candida albicans/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Fluoroquinolonas/síntesis química , Fluoroquinolonas/química , Glicosilación , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Penicillium chrysogenum/efectos de los fármacos , Relación Estructura-ActividadRESUMEN
Since their discovery over 5 decades ago, quinolone antibiotics have found enormous success as broad spectrum agents that exert their activity through dual inhibition of bacterial DNA gyrase and topoisomerase IV. Increasing rates of resistance, driven largely by target-based mutations in the GyrA/ParC quinolone resistance determining region, have eroded the utility and threaten the future use of this vital class of antibiotics. Herein we describe the discovery and optimization of a series of 4-(aminomethyl)quinolin-2(1H)-ones, exemplified by 34, that inhibit bacterial DNA gyrase and topoisomerase IV and display potent activity against ciprofloxacin-resistant Gram-negative pathogens. X-ray crystallography reveals that 34 occupies the classical quinolone binding site in the topoisomerase IV-DNA cleavage complex but does not form significant contacts with residues in the quinolone resistance determining region.
Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Fluoroquinolonas/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Inhibidores de Topoisomerasa II/farmacología , Antibacterianos/síntesis química , Antibacterianos/metabolismo , Antibacterianos/toxicidad , Sitios de Unión , Línea Celular Tumoral , Girasa de ADN/metabolismo , Topoisomerasa de ADN IV/antagonistas & inhibidores , Topoisomerasa de ADN IV/química , Fluoroquinolonas/síntesis química , Fluoroquinolonas/metabolismo , Fluoroquinolonas/toxicidad , Bacterias Gramnegativas/enzimología , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad , Inhibidores de Topoisomerasa II/síntesis química , Inhibidores de Topoisomerasa II/metabolismo , Inhibidores de Topoisomerasa II/toxicidadRESUMEN
BACKGROUND: The present work is an extension of ongoing efforts toward the development and identification of new molecules as monotherapy displaying anti-inflammatory and anti-infective activities and a wide-range of gastrointestinal selectivity. A series of novel set of trisubstituted thiazole compounds (AR-17a to AR-27a) have synthesized and evaluated for their in-vitro and in-vivo anti-inflammatory activities. Synthesized trisubstituted thiazole compounds were also evaluated for their potential antibacterial activity against clinical pathogens causing infectious disease. MATERIAL AND METHOD: The structures of synthesized compounds were characterized by FTIR, 1H NMR, Mass spectroscopic techniques and evaluated for their in-vitro and in-vivo anti-inflammatory effects using the human red blood cell (HRBC) membrane stabilization method and a carrageenan-induced rat paw oedema model, respectively, Diclofenac sodium and Ibuprofen were used as standard drugs. The synthesized compounds AR-17atoAR-27a screened for their in-vitro antibacterial activity against the gram-positive bacteria Staphylococcus aureus (ATCC25923) and Enterococcus faecalis (ATCC29212) and the gram-negative bacteria Escherichia coli (ATCC8739) and Pseudomonas aeruginosa (ATCC9027) using ciprofloxacin and cefdinir as standard drugs. RESULT: Compounds AR-17a and AR-27a elicited maximum anti-inflammatory activity, providing 59% and 61% protection at 20mg/kg, respectively, in the inflamed paw model. Among the tested compounds, AR-17a (6.25), (54) and AR-27a (1.56), (52) had the least minimum inhibitory concentration values and the highest zone of inhibition, indicating their marked antibacterial activities. The lowest conc. were observed at 1.56, 6.25µg/mL for inhibition of bacteria by most of the compounds. CONCLUSION: Novel set of trisubstituted thiazole compounds (AR-17a to AR-27a) have synthesized and characterized successfully. The preliminary screening revealed that these compounds possess promising anti-inflammatory and antibacterial activities. In addition, the objective of the study was achieved with few of the promising structures like AR-17a to AR-27a, which are prove to be potential monotherapy candidates for the treatment of chronic inflammatory diseases and bacterial infections.
Asunto(s)
Antibacterianos/farmacología , Antiinflamatorios/farmacología , Tiazoles/farmacología , Animales , Antibacterianos/síntesis química , Antiinflamatorios/síntesis química , Edema/tratamiento farmacológico , Femenino , Fluoroquinolonas/síntesis química , Fluoroquinolonas/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Masculino , Pruebas de Sensibilidad Microbiana , Ratas , Relación Estructura-Actividad , Tiazoles/síntesis químicaRESUMEN
It is known that resistance of bacteria is one of the major issues in drug treatment. To cope this issue, it is required to synthesize new analogues which contest against mutated bacteria. This research study included synthesis of several derivatives of moxifloxacin by adding different phenol and alkyl halide at third position of carboxylic group with esterification reaction and the structures of synthesized derivatives were characterized by spectroscopic techniques i.e. 1H NMR, FT-IR and mass-spectrometry. In continuation, antimicrobial activities of the analogues were also evaluated against number of Gram-positive, Gram-negative bacteria and fungi. The experimental results of novel derivatives exhibit significant antibacterial and antifungal profile in which so many synthesized derivatives influenced a similar and enhanced activity against selected microbes that were S. typhi, P. mirabilis, P. aeruginosa, S. flexneri, B. subtilis as compared to the moxifloxacin. Moreover, few innovative derivatives were also produced better anti-fungal activity against F. solani and T. rubrum. Furthermore, the enzymatic activity of all analogues has been analyzed against urease and carbonic anhydrase and concluded that C2 was selected inhibitor of urease enzyme.
Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Moxifloxacino/química , Antibacterianos/síntesis química , Antifúngicos/síntesis química , Evaluación Preclínica de Medicamentos , Ésteres/química , Fluoroquinolonas/síntesis química , Fluoroquinolonas/química , Fluoroquinolonas/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Moxifloxacino/farmacología , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Antimicrobial resistance in bacteria is frightening, especially resistance in Gram-negative Bacteria (GNB). In 2017, the World Health Organization (WHO) published a list of 12 bacteria that represent a threat to human health, and among these, a majority of GNB. Antibiotic resistance is a complex and relatively old phenomenon that is the consequence of several factors. The first factor is the vertiginous drop in research and development of new antibacterials. In fact, many companies simply stop this R&D activity. The finding is simple: there are enough antibiotics to treat the different types of infection that clinicians face. The second factor is the appearance and spread of resistant or even multidrug-resistant bacteria. For a long time, this situation remained rather confidential, almost anecdotal. It was not until the end of the 1980s that awareness emerged. It was the time of Vancomycin-Resistance Enterococci (VRE), and the threat of Vancomycin-Resistant MRSA (Methicillin-Resistant Staphylococcus aureus). After this, there has been renewed interest but only in anti-Gram positive antibacterials. Today, the threat is GNB, and we have no new molecules with innovative mechanism of action to fight effectively against these bugs. However, the war against antimicrobial resistance is not lost. We must continue the fight, which requires a better knowledge of the mechanisms of action of anti-infectious agents and concomitantly the mechanisms of resistance of infectious agents.
Asunto(s)
Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Drogas en Investigación/uso terapéutico , Enterobacteriaceae/efectos de los fármacos , Salud Global/tendencias , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/patogenicidad , Acinetobacter baumannii/fisiología , Aminoglicósidos/síntesis química , Aminoglicósidos/economía , Aminoglicósidos/uso terapéutico , Antibacterianos/síntesis química , Antibacterianos/economía , Aprobación de Drogas/organización & administración , Drogas en Investigación/síntesis química , Drogas en Investigación/economía , Enterobacteriaceae/patogenicidad , Enterobacteriaceae/fisiología , Fluoroquinolonas/síntesis química , Fluoroquinolonas/economía , Fluoroquinolonas/uso terapéutico , Salud Global/economía , Glicopéptidos/síntesis química , Glicopéptidos/economía , Glicopéptidos/uso terapéutico , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/patogenicidad , Bacterias Gramnegativas/fisiología , Infecciones por Bacterias Gramnegativas/microbiología , Infecciones por Bacterias Gramnegativas/patología , Humanos , Macrólidos/síntesis química , Macrólidos/economía , Macrólidos/uso terapéutico , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/patogenicidad , Pseudomonas aeruginosa/fisiología , beta-Lactamas/síntesis química , beta-Lactamas/economía , beta-Lactamas/uso terapéuticoRESUMEN
Different studies about the anticancer potential of several medically used antibacterial fluoroquinolones have been established. Fluoroquinolone derivatives, like some anti-cancer drugs, such as doxorubicin, can achieve antitumor activity via poisoning of type II human DNA topoisomerases. Interestingly, structural features required for the anticancer activity of quinolones have been determined. Most of the chemical modifications required to convert antibacterially acting fluoroquinolones into their anticancer analogs were at position 7 and the carboxylic group at position 3. This review highlights the antitumor potential of fluoroquinolones in general and summarizes the chemical modifications carried out on fluoroquinolones to become anticancer agents. Moreover, the review gives a quick recap on metal ion chelates with fluoroquinolones and their substantial role in topoisomerase poisoning and antitumor potential improvement. Hence, it should be highly interesting for researchers attempting to design and synthesize novel anticancer fluoroquinolone candidates.
Asunto(s)
Antibacterianos/farmacología , Antineoplásicos/farmacología , ADN-Topoisomerasas de Tipo II/metabolismo , Fluoroquinolonas/farmacología , Neoplasias/tratamiento farmacológico , Inhibidores de Topoisomerasa II/farmacología , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Bacterias/efectos de los fármacos , Fluoroquinolonas/síntesis química , Fluoroquinolonas/química , Humanos , Estructura Molecular , Neoplasias/metabolismo , Inhibidores de Topoisomerasa II/síntesis química , Inhibidores de Topoisomerasa II/químicaRESUMEN
Fluoroquinolones substituted with N-1 biphenyl and napthyl groups were discovered to act as catalytically inhibitors of human topoisomerases I and II, and to possess anti-proliferative activity in vivo. Structural requirements for these novel quinolones to inhibit catalytic activity of human topoisomerase I have not been explored. In this work novel derivatives of the N-1 biphenyl fluoroquinolone were designed, synthesized and evaluated to understand structural requirements of the C-3 carboxylic acid, C-6 fluorine, C-7 aminomethylpyrrolidine, C-8 methoxy, and the N-1 biphenyl functional groups for hTopoI inhibition. Characterization of each analog for inhibition of hTopoI catalytic inhibition reveals critical insight into structural requirements of these novel quinolones for activity. Additionally, results of DNA binding and modeling studies suggest that N-1 biphenyl fluoroquinolones intercalate between the DNA base pairs with the N-1 biphenyl functional group, rather than the quinolone core, and that this mode of DNA intercalation contributes to inhibition of hTopoI by these novel structures. The results presented here support further development and evaluation of N-1 biphenyl fluoroquinolone analogs as a novel class of anti-cancer agents that act through catalytic inhibition of hTopoI.
Asunto(s)
Compuestos de Bifenilo/farmacología , ADN-Topoisomerasas de Tipo I/metabolismo , Fluoroquinolonas/farmacología , Inhibidores de Topoisomerasa I/farmacología , Compuestos de Bifenilo/síntesis química , Compuestos de Bifenilo/química , Relación Dosis-Respuesta a Droga , Fluoroquinolonas/síntesis química , Fluoroquinolonas/química , Humanos , Estructura Molecular , Relación Estructura-Actividad , Inhibidores de Topoisomerasa I/síntesis química , Inhibidores de Topoisomerasa I/químicaRESUMEN
A series of new fluoroquinolone analogs (3-18) were prepared, in three steps, by substituting chloro esters and esters with cyclic amines on the C-7 endo-nortropine derivatives of difluoroquinolone acid. All the synthesized compounds displayed good MIC against the Staphylococcus aureus when initially screened for Escherichia coli, S. aureus, Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa. The molecules were further evaluated for their antibacterial activity against fluoroquinolone-resistant strains of S. aureus and for cytotoxic assay. Based on the results, five of the sixteen compounds displayed the potential to be developed further for treatment against fluoroquinolone-resistant strains of S. aureus.
Asunto(s)
Antibacterianos/síntesis química , Infecciones Bacterianas/tratamiento farmacológico , Fluoroquinolonas/síntesis química , Nortropanos/química , Aminas/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Farmacorresistencia Bacteriana , Ésteres/química , Fluoroquinolonas/farmacología , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-ActividadRESUMEN
A series of new 1,2,4-triazole and 1,3,4-oxadiazole derivatives was obtained via several steps sequential reactions of phenyl piperazine. Then, these compounds were converted to the corresponding fluoroquinolone hybrids via one pot three component Mannich reaction. All the reactions were examined under conventional and microwave mediated conditions, and optimum conditions were determined. The effect of different solvents and microwave power on microwave prompted reactions was investigated as well. All the newly synthesized compounds were characterized by FTIR, 1H NMR, 13C NMR and EI MS spectral techniques. The antimicrobial activity, DNA gyrase and Topoisomerase IV inhibition potentials were performed. The results obtained showed that fluoroquinolone hybrids possess good antimicrobial activity. Moreover, Fluoroquinolone-azole-piperazine hybrids synthesized in the present study displayed excellent DNA gyrase inhibition. To unveil the interaction mode of compounds to receptor, a molecular docking study was performed. With an average least binding energy of -9.5â¯kcal/mol, all compounds were found to have remarkable inhibitory potentials against DNA gyrase (E. coli).
Asunto(s)
Antibacterianos/farmacología , Fluoroquinolonas/farmacología , Piperazinas/farmacología , Triazoles/farmacología , Antibacterianos/síntesis química , Antibacterianos/metabolismo , Girasa de ADN/metabolismo , Topoisomerasa de ADN IV/antagonistas & inhibidores , Topoisomerasa de ADN IV/metabolismo , Enterococcus faecalis/efectos de los fármacos , Proteínas de Escherichia coli/antagonistas & inhibidores , Proteínas de Escherichia coli/metabolismo , Fluoroquinolonas/síntesis química , Fluoroquinolonas/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/enzimología , Pruebas de Sensibilidad Microbiana , Microondas , Simulación del Acoplamiento Molecular , Piperazinas/síntesis química , Piperazinas/metabolismo , Staphylococcus aureus/efectos de los fármacos , Inhibidores de Topoisomerasa II/síntesis química , Inhibidores de Topoisomerasa II/metabolismo , Inhibidores de Topoisomerasa II/farmacología , Triazoles/síntesis química , Triazoles/metabolismoRESUMEN
Fluoroquinolones represent an interesting synthetic class of antimicrobial agents with broad spectrum and potent activity. Since the discovery of nalidixic acid, the prototype of quinolones, several structural modifications to the quinolone nucleus have been carried out for improvement of potency, spectrum of activity, and to understand their structure activity relationship (SAR). The C-7 substituent was reported to have a major impact on the activity. Accordingly, Substitution at C-7 or its N-4-piperazinyl moiety was found to affect potency, bioavailability, and physicochemical properties. Also, it can increase the affinity towards mammalian topoisomerases that may shift quinolones from antibacterial to anticancer candidates. Moreover, the presence of DNA topoisomerases in both eukaryotic and prokaryotic cells makes them excellent targets for chemotherapeutic intervention in antibacterial and anticancer therapies. Based on this concept, several fluoroquionolones derivatives have been synthesized and biologically evaluated as antibacterial, antituberculosis, antiproliferative, antiviral and antifungal agents. This review is an attempt to focus on the therapeutic prospects of fluoroquinolones with an updated account on their atypical applications such as antitubercular and anticancer activities.