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1.
Reprod Sci ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38691315

RESUMO

The current study aimed to evaluate the serum levels of nitric oxide (NO) and adropin in males with non-alcoholic fatty liver disease (NAFLD) induced erectile dysfunction (ED) and NAFLD patients without ED and controls. The current study selected 165 participants from the hepatology department from November 2021 to November 2022. The patients were either suffering from NAFLD with normal liver functions or non-alcoholic steatohepatitis with abnormal liver functions. They were diagnosed by abdominal ultrasonography. Participants were evaluated using the validated Arabic version of the International Index of Erectile Function (ArIIEF-5), the Arabic form of the Generalized Anxiety Disorder-7 (GAD-7) questionnaire and the Patient Health Questionnaire-9 (PHQ-9). Noteworthy, there were significant positive correlations between ArIIEF-5 score, NO, adropin and total testosterone (r = 0.380, p = 0.001; r = 0.507, p = < 0.001; r = 0.246, p = 0.038, respectively). Meanwhile, there were significant negative correlations between ArIIEF-5 score, creatinine, duration of the disease and scores of GAD-7 and PHQ-9 (r = -0.656, p = < 0.001; r = -0.368, p = 0.002; r = -0.663, p = < 0.001; r = -0.248, p = 0.037, respectively). Finally, a linear regression analysis revealed that GAD-7, creatinine, and adropin were the only strong independent predictors of ArIIEF-5, as the 95% confidence interval in the form of upper and lower bounds was -0.349, -0.843, p < 0.001, -6.507, -18.402, p < 0.001, 0.476, 0.117, and p 0.002, respectively. Impaired NO and adropin levels play a potential role in the development of ED in patients with NAFLD.

2.
Int J Antimicrob Agents ; 63(5): 107160, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38537721

RESUMO

In a vast majority of bacteria, protozoa and plants, the methylerythritol phosphate (MEP) pathway is utilized for the synthesis of isopentenyl diphosphate (IDP) and dimethylallyl diphosphate (DMADP), which are precursors for isoprenoids. Isoprenoids, such as cholesterol and coenzyme Q, play a variety of crucial roles in physiological activities, including cell-membrane formation, protein degradation, cell apoptosis, and transcription regulation. In contrast, humans employ the mevalonate (MVA) pathway for the production of IDP and DMADP, rendering proteins in the MEP pathway appealing targets for antimicrobial agents. This pathway consists of seven consecutive enzymatic reactions, of which 4-diphosphocytidyl-2C-methyl-D-erythritol synthase (IspD) and 2C-methyl-D-erythritol 2,4-cyclodiphosphate synthase (IspF) catalyze the third and fifth steps, respectively. In this study, we characterized the enzymatic activities and protein structures of Helicobacter pylori IspDF and Acinetobacter baumannii IspD. Then, using the direct interaction-based thermal shift assay, we conducted a compound screening of an approved drug library and identified 27 hit compounds potentially binding to AbIspD. Among them, two natural products, rosmarinic acid and tanshinone IIA sodium sulfonate, exhibited inhibitory activities against HpIspDF and AbIspD, by competing with one of the substrates, MEP. Moreover, tanshinone IIA sodium sulfonate also demonstrated certain antibacterial effects against H. pylori. In summary, we identified two IspD inhibitors from approved ingredients, broadening the scope for antibiotic discovery targeting the MEP pathway.


Assuntos
Acinetobacter baumannii , Antibacterianos , Helicobacter pylori , Hemiterpenos , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/enzimologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/enzimologia , Antibacterianos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/metabolismo , Produtos Biológicos/farmacologia , Produtos Biológicos/química , Compostos Organofosforados/farmacologia , Humanos , Transferases (Outros Grupos de Fosfato Substituídos)/antagonistas & inibidores , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo
3.
Arch Pharm (Weinheim) ; 357(4): e2300656, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38304944

RESUMO

Designing novel candidates as potential antibacterial scaffolds has become crucial due to the lack of new antibiotics entering the market and the persistent rise in multidrug resistance. Here, we describe a new class of potent antibacterial agents based on a 5-aryl-N2,N4-dibutylpyrimidine-2,4-diamine scaffold. Structural optimization focused on the 5-aryl moiety and the bioisosteric replacement of the side chain linker atom. Screening of the synthesized compounds focused on a panel of bacterial strains, including gram-positive Staphylococcus aureus strains (Newman MSSA, methicillin- and vancomycin-resistant), and the gram-negative Escherichia coli (ΔAcrB strain). Several compounds showed broad-spectrum antibacterial activity with compound 12, bearing a 4-chlorophenyl substituent, being the most potent among this series of compounds. This frontrunner compound revealed a minimum inhibitory concentration (MIC) value of 1 µg/mL against the S. aureus strain (Mu50 methicillin-resistant S. aureus/vancomycin-intermediate S. aureus) and an MIC of 2 µg/mL against other tested strains. The most potent derivatives were further tested against a wider panel of bacteria and evaluated for their cytotoxicity, revealing further potent activities toward Streptococcus pneumoniae, Enterococcus faecium, and Enterococcus faecalis. To explore the mode of action, compound 12 was tested in a macromolecule inhibition assay. The obtained data were supported by the safety profile of compound 12, which possessed an IC50 of 12.3 µg/mL against HepG2 cells. The current results hold good potential for a new class of extended-spectrum antibacterial agents.


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus , Relação Estrutura-Atividade , Bactérias , Pirimidinas/farmacologia , Testes de Sensibilidade Microbiana
4.
Chem Commun (Camb) ; 60(7): 870-873, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38164786

RESUMO

Herein, we present the first application of target-directed dynamic combinatorial chemistry (tdDCC) to the whole complex of the highly dynamic transmembrane, energy-coupling factor (ECF) transporter ECF-PanT in Streptococcus pneumoniae. In addition, we successfully employed the tdDCC technique as a hit-identification and -optimization strategy that led to the identification of optimized ECF inhibitors with improved activity. We characterized the best compounds regarding cytotoxicity and performed computational modeling studies on the crystal structure of ECF-PanT to rationalize their binding mode. Notably, docking studies showed that the acylhydrazone linker is able to maintain the crucial interactions.


Assuntos
Proteínas de Bactérias , Streptococcus pneumoniae , Modelos Moleculares , Proteínas de Bactérias/química
5.
Urologia ; 91(1): 154-158, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37334432

RESUMO

INTRODUCTION: We aimed to assess the sexual and the reproductive functions in males post COVID-19 infection in Beni-Suef Governorate. METHODS: One hundred men were recruited in the current study. All participants were assessed by the Arabic validated version of the International Index of the Erectile Function 5 (ArIIEF-5), semen analysis, and Hospital Depression and Anxiety Scale (HADS). Finally, morning testosterone serum level was measured. RESULTS: There were significant decreases in the sperm total motility, the ArIIEF-5 score, and serum total testosterone in the post COVID-19 patients after 3 months when compared to the controls. However, there were significant increases in the sperm total motility, the ArIIEF-5 score, and serum total testosterone in the post COVID-19 patients after 6 months group when compared to the post COVID-19 patients after 3 months group. Moreover, there was a significant increase in the HADS score in the post COVID-19 patients after 3 months when compared to the controls. In contrast, there was a significant decrease in the HADS score in the post COVID-19 patients after 6 months when compared to the post COVID-19 patients after 3 months. CONCLUSION: Our study had shown temporary impairment of sexual and reproductive functions in post COVID-19 convalescent males especially after 6 months from the onset of the infection.


Assuntos
COVID-19 , Disfunção Erétil , Humanos , Masculino , Estudos Transversais , Testosterona , Egito , Sêmen
6.
Adv Sci (Weinh) ; 10(5): e2204443, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36596691

RESUMO

Pseudomonas aeruginosa (PA) is an opportunistic human pathogen, which is involved in a wide range of dangerous infections. It develops alarming resistances toward antibiotic treatment. Therefore, alternative strategies, which suppress pathogenicity or synergize with antibiotic treatments are in great need to combat these infections more effectively. One promising approach is to disarm the bacteria by interfering with their quorum sensing (QS) system, which regulates the release of various virulence factors as well as biofilm formation. Herein, this work reports the rational design, optimization, and in-depth profiling of a new class of Pseudomonas quinolone signaling receptor (PqsR) inverse agonists. The resulting frontrunner compound features a pyrimidine-based scaffold, high in vitro and in vivo efficacy, favorable pharmacokinetics as well as clean safety pharmacology characteristics, which provide the basis for potential pulmonary as well as systemic routes of administration. An X-ray crystal structure in complex with PqsR facilitated further structure-guided lead optimization. The compound demonstrates potent pyocyanin suppression, synergizes with aminoglycoside antibiotic tobramycin against PA biofilms, and is active against a panel of clinical isolates from bronchiectasis patients. Importantly, this in vitro effect translated into in vivo efficacy in a neutropenic thigh infection model in mice providing a proof-of-principle for adjunctive treatment scenarios.


Assuntos
Agonismo Inverso de Drogas , Quinolonas , Humanos , Animais , Camundongos , Proteínas de Bactérias , Biofilmes , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Pseudomonas aeruginosa
7.
Bioorg Chem ; 127: 105977, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35779404

RESUMO

The transcription factor NF-κB is a pivotal mediator of chronic inflammatory and autoimmune diseases. Based on our previously published dual EGFR/NF-κB inhibitors, we designed and synthesized new thiourea quinazoline derivatives that retained only the NF-κB inhibitory activity. Several congeners displayed a strong suppression of NF-κB activity in a reporter gene assay, yet low cytotoxicity, and were further evaluated in differentiated macrophage-like THP-1 cells. The compounds exhibited a strong inhibition of IL-6 and, less potently, of TNFα release, which was accompanied by a selective induction of macrophage cell death. The mode of action was investigated with a selected inhibitor, 18, revealing that the translocation of p65/RelA to the nucleus but not its release from the IκB complex was inhibited. Eventually, 18 was identified as the first small molecule inhibitor affecting only the phosphorylation of p65-Ser468 but not of Ser536, which may be causally related to the retention of NF-κB in the cytoplasm. Altogether, our novel NF-κB inhibitors seem applicable for the suppression of cytokine release and the additional selective depletion of activated macrophages in various inflammatory diseases.


Assuntos
NF-kappa B , Feniltioureia , Anti-Inflamatórios/farmacologia , Receptores ErbB/metabolismo , Lipopolissacarídeos , NF-kappa B/metabolismo , Fosforilação
8.
Pharmaceuticals (Basel) ; 15(7)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35890077

RESUMO

For many inflammatory diseases, new effective drugs with fewer side effects are needed. While it appears promising to target the activation of the central pro-inflammatory transcription factor NF-κB, many previously discovered agents suffered from cytotoxicity. In this study, new alkylthiourea quinazoline derivatives were developed that selectively inhibit the activation of NF-κB in macrophage-like THP-1 cells while showing low general cytotoxicity. One of the best compounds, 19, strongly inhibited the production of IL-6 (IC50 = 0.84 µM) and, less potently, of TNFα (IC50 = 4.0 µM); in comparison, the reference compound, caffeic acid phenethyl ester (CAPE), showed IC50s of 1.1 and 11.4 µM, respectively. Interestingly, 19 was found to block the translocation of the NF-κB dimer to the nucleus, although its release from the IκB complex was unaffected. Furthermore, 19 suppressed the phosphorylation of NF-κB-p65 at Ser468 but not at Ser536; however, 19 did not inhibit any kinase involved in NF-κB activation. The only partial suppression of p65 phosphorylation might be associated with fewer side effects. Since several compounds selectively induced cell death in activated macrophage-like THP-1 cells, they might be particularly effective in various inflammatory diseases that are exacerbated by excess activated macrophages, such as arteriosclerosis and autoimmune diseases.

9.
J Med Chem ; 65(13): 8869-8880, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35709475

RESUMO

Here, we report on a potent class of substituted ureidothiophenes targeting energy-coupling factor (ECF) transporters, an unexplored target that is not addressed by any antibiotic in the market. Since the ECF module is crucial for the vitamin transport mechanism, the prevention of substrate uptake should ultimately lead to cell death. By utilizing a combination of virtual and functional whole-cell screening of our in-house library, the membrane-bound protein mediated uptake of folate could be effectively inhibited. Structure-based optimization of our hit yielded low-micromolar inhibitors, whereby the most active compounds showed in addition potent antimicrobial activities against a panel of clinically relevant Gram-positive pathogens without significant cytotoxic effects.


Assuntos
Proteínas de Bactérias , Proteínas de Membrana , Proteínas de Bactérias/metabolismo , Transporte Biológico , Membrana Celular/metabolismo , Ácido Fólico/metabolismo , Proteínas de Membrana/metabolismo , Modelos Moleculares
10.
Pharmaceuticals (Basel) ; 15(5)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35631457

RESUMO

In today's global plan to completely eradicate hepatitis C virus (HCV), the essential list of medications used for HCV treatment are direct-acting antivirals (DAAs), as interferon-sparing regimens have become the standard-of-care (SOC) treatment. HCV nonstructural protein 5A (NS5A) inhibitors are a very common component of these regimens. Food and Drug Administration (FDA)-approved NS5A inhibitors, although very potent, do not have the same potency against all eight genotypes of HCV. Therefore, this study aims to synthesize NS5A inhibitor analogues with high potency pan-genotypic activity and high metabolic stability. Starting from an NS5A inhibitor scaffold previously identified by our research group, we made several modifications. Two series of compounds were created to test the effect of changing the length and spatial conformation (para-para vs. meta-meta-positioned bis-imidazole-proline-carbamate), replacing amide groups in the linker with imidazole groups, as well as different end-cap compositions and sizes. The frontrunner inhibits genotype 1b (Con1) replicon, with an EC50 value in the picomolar range, and showed high genotypic coverage with nanomolar range EC50 values against four more genotypes. This together with its high metabolic stability (t½ > 120 min) makes it a potential preclinical candidate.

11.
ACS Omega ; 7(12): 10447-10457, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35382267

RESUMO

Now the wide use of nanooxides is attributed to their remarkable collection of properties. Nanocomposites have an impressive variety of important applications. A thermal decomposition approach provides a more optimistic method for nanocrystal synthesis due to the low cost, high efficiency, and expectations for large-scale production. Therefore, in this study a new eco-friendly nanooxide composite with sorption characteristics for europium (Eu(III)) and strontium (Sr(II)) was synthesized by a one-step thermal treatment process using earth-abundant tafla clay as a starting material to prepare a modified tafla (M-Taf) nanocomposite. The synthesized nancomposite was characterized by different techniques before and after sorption processes. Different factors that affected the sorption behavior of Eu(III) and Sr(II) in aqueous media by the M-Taf nanocomposite were studied. The results obtained illustrated that the kinetics of sorption of Eu(III) and Sr(II) by the M-Taf nanocomposite are obeyed according to the pseudo-second order and controlled by a Langmuir isotherm model with maximum sorption capacities (Q max) of 25.5 and 23.36 mg/g for Eu(III) and Sr(II), respectively. Also, this novel low-cost and eco-friendly sorbent has promising properties and can be used to separate and retain some radionuclides in different applications.

12.
Cureus ; 14(1): e21031, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35154999

RESUMO

INTRODUCTION: Total hip replacement (THR) in the neck of femur fracture in the elderly is associated with a higher risk of dislocation compared to hemiarthroplasty of hip or total hip replacement in the native hip. There is uncertainty regarding combining surgical approach, femoral head size, and the usage of single bearing or dual mobility to reduce the risk of dislocation. This study looks into the bearing of the prosthesis for posterior or lateral surgical hip approach as well as their head size to give a stable hip to these vulnerable groups of patients. METHODS: Initial data were collected retrospectively from February 2017 till May 2019 from the electronic records database and clinical notes. Patients included in the study had a femoral neck fracture (age >60 years) who underwent a total hip replacement. Subsequent data were collected prospectively from June 2019 to July 2020. RESULTS: High rate of dislocation was found with posterior approach and single bearing prosthesis. However, if dual mobility prosthesis was used while using the posterior approach the dislocation rate was very low. Also, with lateral approach and single bearing prosthesis using large femoral head size, the dislocation rate was negligible. CONCLUSIONS: We recommend a dual mobility prosthesis for posterior approach THR and lateral approach with single-bearing hip replacement with large size femoral head. The dislocation rate is low using this principle irrespective of the surgical approach.

13.
Bioorg Med Chem Lett ; 59: 128531, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35007723

RESUMO

Bacterial resistance to currently used antibiotics demands the development of novel antibacterial agents with good safety margins and sufficient efficacy against multi-drug resistant isolates. We have previously described the synthesis of N-butyl-2-(butylthio)quinazolin-4-amine (I) as an optimized hit with broad-spectrum antibacterial activity and low cytotoxicity. In addition, we have identified a potential growing vector for this series of compounds. Herein, we describe further hit optimization which includes systematic diversifications of both the benzenoid part and the substituents at position 6 and 7 of compound I. Growing of the molecule beside the core modifications yielded several compounds with remarkable anti(myco)bacterial activity against a panel of pathogenic bacteria, including drug-resistant strains. Compound 12 showed a 2-4 fold improvement in activity than I against S. aureus Newman, S. pneumoniae DSM-20566 and E. faecalis DSM-20478. The compounds also showed a good safety profile towards human HepG2 cells.


Assuntos
Antibacterianos/farmacologia , Derivados de Benzeno/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Quinazolinas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Derivados de Benzeno/química , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Quinazolinas/síntese química , Quinazolinas/química , Relação Estrutura-Atividade
14.
ChemMedChem ; 17(5): e202100679, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34918860

RESUMO

The enzymes of the 2-C-methylerythritol-d-erythritol 4-phosphate (MEP) pathway (MEP pathway or non-mevalonate pathway) are responsible for the synthesis of universal precursors of the large and structurally diverse family of isoprenoids. This pathway is absent in humans, but present in many pathogenic organisms and plants, making it an attractive source of drug targets. Here, we present a high-throughput screening approach that led to the discovery of a novel fragment hit active against the third enzyme of the MEP pathway, PfIspD. A systematic SAR investigation afforded a novel chemical structure with a balanced activity-stability profile (16). Using a homology model of PfIspD, we proposed a putative binding mode for our newly identified inhibitors that sets the stage for structure-guided optimization.


Assuntos
Eritritol , Fosfatos Açúcares , Eritritol/análogos & derivados , Eritritol/química , Eritritol/metabolismo , Eritritol/farmacologia , Humanos , Fosfatos Açúcares/química
15.
Eur J Med Chem ; 229: 114034, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34959173

RESUMO

Herein, we report the discovery of several NS5A inhibitors with potency against HCV genotype 1b in the picomolar range. Compounds (15, 33) were of extremely high potency against HCV genotype 1b (EC50 ≈ 1 pM), improved activity against genotype 3a (GT 3a) and good metabolic stability. We studied the impact of changing the cap conformation relative to the diphenylethyne core and/or compound symmetry on both potency and metabolic stability. The analogs obtained exhibited improved potency against HCV genotypes 1a, 1b, 3a and 4a compared to the clinically approved candidate daclatasvir with EC50 values in the low picomolar range and SI50s > 7 orders of magnitude. Compound 15, a symmetrically m-, m'-substituted diphenyl ethyne analog, was 150-fold more potent than daclatasvir against GT 3a, while compound 33, an asymmetrically m-, p-substituted diphenyl ethyne analog, was 35-fold more potent than daclatasvir against GT 3a. In addition, compound 15 exhibited a higher resistance barrier than daclatasvir against genotype 1b.


Assuntos
Acetileno/análogos & derivados , Antivirais/química , Desenho de Fármacos , Hepacivirus/genética , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Proteínas não Estruturais Virais/antagonistas & inibidores , Acetileno/química , Antivirais/metabolismo , Antivirais/farmacologia , Sítios de Ligação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Farmacorresistência Viral/efeitos dos fármacos , Genótipo , Hepacivirus/metabolismo , Humanos , Conformação Molecular , Simulação de Acoplamento Molecular , RNA Polimerase Dependente de RNA/metabolismo , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/efeitos dos fármacos
16.
Appl Radiat Isot ; 180: 110058, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34922309

RESUMO

In this study a new low-cost carbonaceous material was prepared from husks of opuntia-ficus-indica as a starting material (precursor) which was accomplished by chemical activation route using H3PO4 impregnation. The material has been identified by different analytical tools. The sorption performance of Cs(I) and Sr(II) from HNO3 solutions was examined through batch system. Variations of the distribution coefficients (Kd) as a function of HNO3 concentration in the range 0.001-5.0 M were presented. Some of separation probabilities were suggested. The results attained signals that the Sr(II) selectivity is higher than that of Cs(I) at high molarities. The retention capacity (qe) of Cs(I) and Sr(II) ions increased with growing temperature. The capacities at 0.001 M HNO3 are 34 and 108 mg/g for Cs(I) and Sr(II), respectively. Whereas, at 2.0 M HNO3 capacities were about 4 and 37 mg/g for each of Cs(I) and Sr (II), respectively. This studies demonstrates that the prepared carbonaceous sorbent is an economically effective sorbent for retention of Cs(I) and Sr(II) species from HNO3 solutions. Cs(I) and Sr(II) removal potential was tested from simulated low- and intermediate-level radioactive waste samples.

17.
Bioorg Chem ; 117: 105422, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34700110

RESUMO

The emergence of bacterial resistance has triggered a multitude of efforts to develop new antibacterial agents. There are many compounds in literature that were reported as potent antibacterial agents, however, they lacked the required safety to mammalian cells or no clear picture about their toxicity profile was presented. Inspired by discovered hit from our in-house library and by previously reported 2,4-diaminosubstituted quinazolines, we describe the design and synthesis of novel 2,4-disubstituted-thioquinazolines (3-13 and 36), 2-thio-4-amino substituted quinazolines (14-33) and 6-substituted 2,4-diamonsubstituted quinazolines (37-39). The synthesized compounds showed potent antibacterial activity against a panel of Gram-positive, efflux deficient E.coli and Mycobacterium smegmatis. The panel also involved resistant strains including methicillin-resistant Staphylococcus aureus, penicillin-resistant Streptococcus pneumoniae, vancomycin-resistant Enterococcus faecalis and vancomycin-resistant Enterococcus faecium, in addition to Mycobacterium smegmatis. The newly synthesized compounds revealed MIC values against the tested strains ranging from 1 to 64 µg/mL with a good safety profile. Most of the 2-thio-4-amino substituted-quinazolines showed significant antimycobacterial activity with the variations at position 2 and 4 offering additional antibacterial activity against the different strains. Compared to previously reported 2,4-diaminosubstituted quinazolines, the bioisosteric replacement of the 2-amino with sulfur offered a successful approach to keep the high antibacterial potency while substantially improving safety profile as indicated by the reduced activity on different cell lines and a lack of hemolytic activity.


Assuntos
Antibacterianos/farmacologia , Quinazolinas/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Células CHO , Sobrevivência Celular/efeitos dos fármacos , Cricetulus , Relação Dose-Resposta a Droga , Enterococcus faecalis/efeitos dos fármacos , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium smegmatis/efeitos dos fármacos , Quinazolinas/síntese química , Quinazolinas/química , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos , Relação Estrutura-Atividade
18.
Eur J Med Chem ; 226: 113797, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34520957

RESUMO

A short and divergent route towards new derivatives of 2-(trifluoromethyl)pyridines as potent inverse agonists of the bacterial target PqsR against Pseudomonas aeruginosa (PA) infections is described. This Gram-negative pathogen causes severe nosocomial infections and common antibiotic treatment options are rendered ineffective due to resistance issues. Based on an earlier identified optimized hit, we conducted derivatization and rigidification attempts employing two central building blocks. The western part of the molecule is built up via a 2-(trifluoromethyl)pyridine head group equipped with a terminal alkyne. The eastern section is then introduced through aryliode motifs exploiting Sonogashira as well as Suzuki-type chemistry. Subsequent modification provided quick access to an array of compounds, allowed for deep SAR insights, and enabled to optimize the hit scaffold into a lead structure of nanomolar potency combined with favorable in vitro ADME/T features.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/agonistas , Pseudomonas aeruginosa/efeitos dos fármacos , Piridinas/farmacologia , Transativadores/agonistas , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piridinas/síntese química , Piridinas/química , Relação Estrutura-Atividade
19.
Molecules ; 26(16)2021 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-34443518

RESUMO

Myxobacteria represent a viable source of chemically diverse and biologically active secondary metabolites. The myxochelins are a well-studied family of catecholate-type siderophores produced by various myxobacterial strains. Here, we report the discovery, isolation, and structure elucidation of three new myxochelins N1-N3 from the terrestrial myxobacterium Corallococcus sp. MCy9049, featuring an unusual nicotinic acid moiety. Precursor-directed biosynthesis (PDB) experiments and total synthesis were performed in order to confirm structures, improve access to pure compounds for bioactivity testing, and to devise a biosynthesis proposal. The combined evaluation of metabolome and genome data covering myxobacteria supports the notion that the new myxochelin congeners reported here are in fact frequent side products of the known myxochelin A biosynthetic pathway in myxobacteria.


Assuntos
Produtos Biológicos/química , Lisina/análogos & derivados , Myxococcales/química , Niacina/química , Vias Biossintéticas/genética , Genoma Bacteriano/genética , Lisina/química , Metaboloma/genética , Myxococcales/genética , Myxococcales/isolamento & purificação , Niacina/isolamento & purificação
20.
Adv Sci (Weinh) ; 8(12): e2004369, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34165899

RESUMO

Pseudomonas aeruginosa (PA) infections can be notoriously difficult to treat and are often accompanied by the development of antimicrobial resistance (AMR). Quorum sensing inhibitors (QSI) acting on PqsR (MvfR) - a crucial transcriptional regulator serving major functions in PA virulence - can enhance antibiotic efficacy and eventually prevent the AMR. An integrated drug discovery campaign including design, medicinal chemistry-driven hit-to-lead optimization and in-depth biological profiling of a new QSI generation is reported. The QSI possess excellent activity in inhibiting pyocyanin production and PqsR reporter-gene with IC50 values as low as 200 and 11 × 10-9 m, respectively. Drug metabolism and pharmacokinetics (DMPK) as well as safety pharmacology studies especially highlight the promising translational properties of the lead QSI for pulmonary applications. Moreover, target engagement of the lead QSI is shown in a PA mucoid lung infection mouse model. Beyond that, a significant synergistic effect of a QSI-tobramycin (Tob) combination against PA biofilms using a tailor-made squalene-derived nanoparticle (NP) formulation, which enhance the minimum biofilm eradicating concentration (MBEC) of Tob more than 32-fold is demonstrated. The novel lead QSI and the accompanying NP formulation highlight the potential of adjunctive pathoblocker-mediated therapy against PA infections opening up avenues for preclinical development.


Assuntos
Biofilmes/efeitos dos fármacos , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Quinolonas/agonistas , Percepção de Quorum/efeitos dos fármacos , Tobramicina/farmacologia , Animais , Modelos Animais de Doenças , Camundongos
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