Phenotypic screening of an in-house library of small molecule purine derivatives against Mycobacterium tuberculosis (Mtb) led to the identification of 2-morpholino-7-(naphthalen-2-ylmethyl)-1,7-dihydro-6H-purin-6-one 10 as a potent antimycobacterial agent with MIC99 of 4 μM. Thorough structure-activity relationship studies revealed the importance of 7-(naphthalen-2-ylmethyl) substitution for antimycobacterial activity, yet opened the possibility of structural modifications at positions 2 and 6 of the purine core. As the result, optimized analogues with 6-amino or ethylamino substitution 56 and 64, respectively, were developed. These compounds showed strong in vitro antimycobacterial activity with MIC of 1 μM against Mtb H37Rv and against several clinically isolated drug-resistant strains, had limited toxicity to mammalian cell lines, medium clearance with respect to phase I metabolic deactivation (27 and 16.8 μL/min/mg), sufficient aqueous solubility (>90 μM) and high plasma stability. Interestingly, investigated purines, including compounds 56 and 64, lacked activity against a panel of Gram-negative and Gram-positive bacterial strains, indicating a specific mycobacterial molecular target. To investigate the mechanism of action, Mtb mutants resistant to hit compound 10 were isolated and their genomes were sequenced. Mutations were found in dprE1 (Rv3790), which encodes decaprenylphosphoryl-β-d-ribose oxidase DprE1, enzyme essential for the biosynthesis of arabinose, a vital component of the mycobacterial cell wall. Inhibition of DprE1 by 2,6-disubstituted 7-(naphthalen-2-ylmethyl)-7H-purines was proved using radiolabelling experiments in Mtb H37Rv in vitro. Finally, structure-binding relationships between selected purines and DprE1 using molecular modeling studies in tandem with molecular dynamic simulations revealed the key structural features for effective drug-target interaction.

• MeSH
• alkoholoxidoreduktasy chemie   MeSH
• antituberkulotika * chemie   MeSH
• bakteriální proteiny metabolismus   MeSH
• Mycobacterium tuberculosis * MeSH
• puriny farmakologie   MeSH
• savci metabolismus   MeSH
• simulace molekulární dynamiky MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

In this study, we have focused on a multiparametric microbiological analysis of the antistaphylococcal action of the iodinated imine BH77, designed as an analogue of rafoxanide. Its antibacterial activity against five reference strains and eight clinical isolates of Gram-positive cocci of the genera Staphylococcus and Enterococcus was evaluated. The most clinically significant multidrug-resistant strains, such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant S. aureus (VRSA), and vancomycin-resistant Enterococcus faecium, were also included. The bactericidal and bacteriostatic actions, the dynamics leading to a loss of bacterial viability, antibiofilm activity, BH77 activity in combination with selected conventional antibiotics, the mechanism of action, in vitro cytotoxicity, and in vivo toxicity in an alternative animal model, Galleria mellonella, were analyzed. The antistaphylococcal activity (MIC) ranged from 15.625 to 62.5 μM, and the antienterococcal activity ranged from 62.5 to 125 μM. Its bactericidal action; promising antibiofilm activity; interference with nucleic acid, protein, and peptidoglycan synthesis pathways; and nontoxicity/low toxicity in vitro and in vivo in the Galleria mellonella model were found to be activity attributes of this newly synthesized compound. In conclusion, BH77 could be rightfully minimally considered at least as the structural pattern for future adjuvants for selected antibiotic drugs. IMPORTANCE Antibiotic resistance is among the largest threats to global health, with a potentially serious socioeconomic impact. One of the strategies to deal with the predicted catastrophic future scenarios associated with the rapid emergence of resistant infectious agents lies in the discovery and research of new anti-infectives. In our study, we have introduced a rafoxanide analogue, a newly synthesized and described polyhalogenated 3,5-diiodosalicylaldehyde-based imine, that effectively acts against Gram-positive cocci of the genera Staphylococcus and Enterococcus. The inclusion of an extensive and comprehensive analysis for providing a detailed description of candidate compound-microbe interactions allows the valorization of the beneficial attributes linked to anti-infective action conclusively. In addition, this study can help with making rational decisions about the possible involvement of this molecule in advanced studies or may merit the support of studies focused on related or derived chemical structures to discover more effective new anti-infective drug candidates.

• MeSH
• antibakteriální látky farmakologie   chemie   MeSH
• antiinfekční látky * farmakologie   MeSH
• Enterococcus MeSH
• methicilin rezistentní Staphylococcus aureus * MeSH
• mikrobiální testy citlivosti MeSH
• rafoxanid farmakologie   MeSH
• Staphylococcus aureus MeSH
• Staphylococcus MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Mycobacterium tuberculosis is an intracellular pathogen and the uptake of the antimycobacterial compounds by host cells is limited. Novel antimycobacterials effective against intracellular bacteria are needed. New N-substituted derivatives of 4-aminosalicylic acid have been designed and evaluated. To achieve intracellular efficacy and selectivity, these compounds were conjugated to tuftsin peptides via oxime or amide bonds. These delivery peptides can target tuftsin- and neuropilin receptor-bearing cells, such as macrophages and various other cells of lung origin. We have demonstrated that the in vitro antimycobacterial activity of the 4-aminosalicylic derivatives against M. tuberculosis H37Rv was preserved in the peptide conjugates. The free drugs were ineffective on infected cells, but the conjugates were active against the intracellular bacteria and have the selectivity on various types of host cells. The intracellular distribution of the carrier peptides was assessed, and the peptides internalize and display mainly in the cytosol in a concentration-dependent manner. The penetration ability of the most promising carrier peptide OT5 was evaluated using Transwell-inserts and spheroids. The pentapeptide exhibited time- and concentration-dependent penetration across the non-contact monolayers. Also, the pentapeptide has a fair penetration rate towards the center of spheroids formed of EBC-1 cells.

• MeSH
• antibakteriální látky farmakologie   MeSH
• antituberkulotika chemie   farmakologie   MeSH
• kyselina aminosalicylová * farmakologie   MeSH
• mikrobiální testy citlivosti MeSH
• Mycobacterium tuberculosis * MeSH
• peptidy chemie   MeSH
• pomocné látky farmakologie   MeSH
• tuftsin * chemie   farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH

Based on successful antitubercular isoniazid scaffold we have designed its "mee-too" analogues by a combination of this drug linked with substituted anilines through pyruvic acid as a bridge. Lipophilicity important for passive diffusion through impenetrable mycobacterial cell wall was increased by halogen substitution on the aniline. We prepared twenty new 2-(2-isonicotinoylhydrazineylidene)propanamides that were assayed against susceptible Mycobacterium tuberculosis H37Rv, nontuberculous mycobacteria, and also multidrug-resistant tuberculous strains (MDR-TB). All the compounds showed excellent activity not only against Mtb. (minimum inhibitory concentrations, MIC, from ≤0.03 μM), but also against M. kansasii (MIC ≥2 μM). The most active molecules have CF3 and OCF3 substituent in the position 4 on the aniline ring. MIC against MDR-TB were from 8 μM. The most effective derivatives were used for the mechanism of action investigation. The treatment of Mtb. H37Ra with tested compounds led to decreased production of mycolic acids and the strains overproducing InhA were more resistant to them. These results confirm that studied compounds inhibit the enoyl-acyl carrier protein reductase (InhA) in mycobacteria. The compounds did not show any cytotoxic and cytostatic activity for HepG2 cells. The amides can be considered as a promising scaffold for antitubercular drug discovery having better antimicrobial properties than original isoniazid together with a significantly improved pharmaco-toxicological profile.

• MeSH
• amidy chemie   metabolismus   farmakologie   terapeutické užití   MeSH
• aniliny chemie   MeSH
• antituberkulotika chemická syntéza   metabolismus   farmakologie   terapeutické užití   MeSH
• bakteriální léková rezistence účinky léků   MeSH
• bakteriální proteiny antagonisté a inhibitory   metabolismus   MeSH
• buňky Hep G2 MeSH
• kyselina pyrohroznová chemie   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• Mycobacterium tuberculosis účinky léků   metabolismus   MeSH
• oxidoreduktasy antagonisté a inhibitory   metabolismus   MeSH
• racionální návrh léčiv * MeSH
• tuberkulóza farmakoterapie   MeSH
• viabilita buněk účinky léků   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Most therapeutic agents used for treating brain malignancies face hindered transport through the blood-brain barrier (BBB) and poor tissue penetration. To overcome these problems, we developed peptide conjugates of conventional and experimental anticancer agents. SynB3 cell-penetrating peptide derivatives were applied that can cross the BBB. Tuftsin derivatives were used to target the neuropilin-1 transport system for selectivity and better tumor penetration. Moreover, SynB3-tuftsin tandem compounds were synthesized to combine the beneficial properties of these peptides. Most of the conjugates showed high and selective efficacy against glioblastoma cells. SynB3 and tandem derivatives demonstrated superior cellular internalization. The penetration profile of the conjugates was determined on a lipid monolayer and Transwell co-culture system with noncontact HUVEC-U87 monolayers as simple ex vivo and in vitro BBB models. Importantly, in 3D spheroids, daunomycin-peptide conjugates possessed a better tumor penetration ability than daunomycin. These conjugates are promising tools for the delivery systems with tunable features.

• MeSH
• antitumorózní látky chemie   farmakokinetika   farmakologie   MeSH
• buněčné sféroidy účinky léků   metabolismus   MeSH
• endoteliální buňky pupečníkové žíly (lidské) MeSH
• glioblastom farmakoterapie   metabolismus   MeSH
• hematoencefalická bariéra metabolismus   MeSH
• krysa rodu rattus MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nádorové buňky kultivované MeSH
• nádory mozku farmakoterapie   metabolismus   MeSH
• neuropilin-1 metabolismus   MeSH
• nosiče léků chemie   farmakokinetika   farmakologie   MeSH
• oligopeptidy chemie   farmakokinetika   farmakologie   MeSH
• penetrační peptidy chemie   farmakokinetika   farmakologie   MeSH
• systémy cílené aplikace léků MeSH
• tuftsin analogy a deriváty   farmakokinetika   farmakologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Based on the isosterism concept, we have designed and synthesized homologous N-alkyl-2-[4-(trifluoromethyl)benzoyl]hydrazine-1-carboxamides (from C1 to C18) as potential antimicrobial agents and enzyme inhibitors. They were obtained from 4-(trifluoromethyl)benzohydrazide by three synthetic approaches and characterized by spectral methods. The derivatives were screened for their inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) via Ellman's method. All the hydrazinecarboxamides revealed a moderate inhibition of both AChE and BuChE, with IC50 values of 27.04-106.75 µM and 58.01-277.48 µM, respectively. Some compounds exhibited lower IC50 for AChE than the clinically used drug rivastigmine. N-Tridecyl/pentadecyl-2-[4-(trifluoromethyl)benzoyl]hydrazine-1-carboxamides were identified as the most potent and selective inhibitors of AChE. For inhibition of BuChE, alkyl chain lengths from C5 to C7 are optimal substituents. Based on molecular docking study, the compounds may work as non-covalent inhibitors that are placed in a close proximity to the active site triad. The compounds were evaluated against Mycobacterium tuberculosis H37Rv and nontuberculous mycobacteria (M. avium, M. kansasii). Reflecting these results, we prepared additional analogues of the most active carboxamide (n-hexyl derivative 2f). N-Hexyl-5-[4-(trifluoromethyl)phenyl]-1,3,4-oxadiazol-2-amine (4) exhibited the lowest minimum inhibitory concentrations within this study (MIC ≥ 62.5 µM), however, this activity is mild. All the compounds avoided cytostatic properties on two eukaryotic cell lines (HepG2, MonoMac6).

• MeSH
• acetylcholinesterasa metabolismus   MeSH
• antiinfekční látky * chemická syntéza   chemie   farmakologie   MeSH
• buňky Hep G2 MeSH
• butyrylcholinesterasa metabolismus   MeSH
• cholinesterasové inhibitory * chemická syntéza   chemie   farmakologie   MeSH
• GPI-vázané proteiny metabolismus   MeSH
• imidazoly * chemická syntéza   chemie   farmakologie   MeSH
• lidé MeSH
• Mycobacterium avium růst a vývoj   MeSH
• Mycobacterium kansasii růst a vývoj   MeSH
• Mycobacterium tuberculosis růst a vývoj   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

The research of novel antimycobacterial drugs represents a cutting-edge topic. Thirty phenolic N-monosubstituted carbamates, derivatives of salicylanilides and 4-chlorophenol, were investigated against Mycobacterium tuberculosis H37Ra, H37Rv including multidrug- and extensively drug-resistant strains, Mycobacterium avium, Mycobacterium kansasii, Mycobacterium aurum and Mycobacterium smegmatis as representatives of nontuberculous mycobacteria (NTM) and for their cytotoxic and cytostatic properties in HepG2 cells. Since salicylanilides are multi-targeting compounds, we determined also inhibition of mycobacterial isocitrate lyase, an enzyme involved in the maintenance of persistent tuberculous infection. The minimum inhibitory concentrations were from ≤0.5 μM for both drug-susceptible and resistant M. tuberculosis and from ≤0.79 μM for NTM with no cross-resistance to established drugs. The presence of halogenated salicylanilide scaffold results into an improved activity. We have verified that isocitrate lyase is not a key target, presented carbamates showed only moderate inhibitory activity (up to 18% at a concentration of 10 μM). Most of the compounds showed no cytotoxicity for HepG2 cells and some of them were without cytostatic activity. Cytotoxicity-based selectivity indexes of several carbamates for M. tuberculosis, including resistant strains, were higher than 125, thus favouring some derivatives as promising features for future development.

• MeSH
• antituberkulotika chemická syntéza   chemie   farmakologie   MeSH
• buňky Hep G2 MeSH
• fenoly chemická syntéza   chemie   farmakologie   MeSH
• isocitrátlyasa antagonisté a inhibitory   metabolismus   MeSH
• karbamáty chemická syntéza   chemie   farmakologie   MeSH
• lidé MeSH
• Mycobacterium tuberculosis účinky léků   enzymologie   MeSH
• salicylanilidy chemická syntéza   chemie   farmakologie   MeSH
• tuberkulóza farmakoterapie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Reflecting the known biological activity of isoniazid-based hydrazones, seventeen hydrazones of 4-(trifluoromethyl)benzohydrazide as their bioisosters were synthesized from various benzaldehydes and aliphatic ketones. The compounds were screened for their in vitro activity against Mycobacterium tuberculosis, nontuberculous mycobacteria (M. avium, M. kansasii), bacterial and fungal strains. The most antimicrobial potent derivatives were also investigated for their cytostatic and cytotoxic properties against three cell lines. Camphor-based molecule, 4-(trifluoromethyl)-N'-(1,7,7-trimethylbicyclo[2.2.1]heptan-2-ylidene)benzohydrazide, exhibited the highest and selective inhibition of M. tuberculosis with the minimum inhibitory concentration (MIC) of 4 µM, while N'-(4-chlorobenzylidene)-4-(trifluoromethyl)benzohydrazide was found to be superior against M. kansasii (MIC = 16 µM). N'-(5-Chloro-2-hydroxybenzylidene)-4-(trifluoromethyl)benzohydrazide showed the lowest MIC values for gram-positive bacteria including methicillin-resistant Staphylococcus aureus as well as against two fungal strains of Candida glabrata and Trichophyton mentagrophytes within the range of ≤0.49-3.9 µM. The convenient substitution of benzylidene moiety at the position 4 or the presence of 5-chloro-2-hydroxybenzylidene scaffold concomitantly with a sufficient lipophilicity are essential for the noticeable antimicrobial activity. This 5-chlorosalicylidene derivative avoided any cytotoxicity on two mammalian cell cultures (HepG2, BMMΦ) up to the concentration of 100 µM, but it affected the growth of MonoMac6 cells.

• MeSH
• antiinfekční látky chemická syntéza   farmakologie   toxicita   MeSH
• buněčné linie MeSH
• buňky Hep G2 MeSH
• Candida glabrata účinky léků   MeSH
• hydrazony chemie   farmakologie   toxicita   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• Mycobacterium avium komplex účinky léků   MeSH
• Mycobacterium kansasii účinky léků   MeSH
• Mycobacterium tuberculosis účinky léků   MeSH
• myši MeSH
• viabilita buněk účinky léků   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Tuberculosis is caused by Mycobacterium tuberculosis, an intracellular pathogen that can survive in host cells, mainly in macrophages. An increase of multidrug-resistant tuberculosis qualifies this infectious disease as a major public health problem worldwide. The cellular uptake of the antimycobacterial agents by infected host cells is limited. Our approach is to enhance the cellular uptake of the antituberculars by target cell-directed delivery using drug-peptide conjugates to achieve an increased intracellular efficacy. In this study, salicylanilide derivatives (2-hydroxy-N-phenylbenzamides) with remarkable antimycobacterial activity were conjugated to macrophage receptor specific tuftsin based peptide carriers through oxime bond directly or by insertion of a GFLG tetrapeptide spacer. We have found that the in vitro antimycobacterial activity of the salicylanilides against M. tuberculosis H37Rv is preserved in the conjugates. While the free drug was ineffective on infected macrophage model, the conjugates were active against the intracellular bacteria. The fluorescently labelled peptide carriers that were modified with different fatty acid side chains showed outstanding cellular uptake rate to the macrophage model cells. The conjugation of the salicylanilides to tuftsin based carriers reduced or abolished the in vitro cytostatic activity of the free drugs with the exception of the palmitoylated conjugates. The conjugates degraded in the presence of rat liver lysosomal homogenate leading to the formation of an oxime bond-linked salicylanilide-amino acid fragment as the smallest active metabolite.

• MeSH
• antituberkulotika chemie   farmakokinetika   farmakologie   MeSH
• buněčné linie MeSH
• krysa rodu rattus MeSH
• lidé MeSH
• multirezistentní tuberkulóza farmakoterapie   MeSH
• Mycobacterium tuberculosis účinky léků   MeSH
• Mycobacterium účinky léků   MeSH
• mykobakteriózy farmakoterapie   MeSH
• salicylanilidy chemie   farmakokinetika   farmakologie   MeSH
• tuberkulóza farmakoterapie   MeSH
• tuftsin analogy a deriváty   farmakokinetika   farmakologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Based on the previously described antimicrobial activity of salicylanilide derivatives, we designed and synthesized novel 2-(phenylcarbamoyl)phenyl 4-substituted benzoates. The most active salicylanilides were selected for esterification by various 4-substituted benzoic acids. These compounds were evaluated in vitro against Mycobacterium tuberculosis, including multidrug-resistant strains, nontuberculous mycobacteria (Mycobacterium avium and Mycobacterium kansasii), and eight bacterial and fungal strains. We also investigated the cytostatic and cytotoxic actions of the esters. The minimum inhibitory concentrations (MICs) against mycobacteria ranged from 0.125 to 8μM. Interestingly, the drug-resistant strains exhibited the highest susceptibility without any cross-resistance with established drugs. 4-Bromo-2-[4-(trifluoromethyl)phenylcarbamoyl]phenyl 4-nitrobenzoate showed the most potent inhibition with MIC values ranging from 0.25 to 2μM. Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus, were inhibited by two derivatives with MIC values of at least 0.49μM, whereas Gram-negative bacteria and most of the tested fungi did not display any marked susceptibility. Benzoates exhibited no cytotoxicity at concentrations up to 50μM but most caused significant cytostasis with IC50 values lower than 10μM. Some cytotoxicity-based selectivity indexes for drug-susceptible and drug-resistant M. tuberculosis as well as Staphylococci were higher than 100. These values indicate that some of these derivatives are promising candidates for future research.

• MeSH
• antibakteriální látky chemická syntéza   chemie   farmakologie   MeSH
• antifungální látky chemická syntéza   chemie   farmakologie   MeSH
• Bacteria účinky léků   MeSH
• bakteriální infekce farmakoterapie   MeSH
• benzoáty chemická syntéza   chemie   farmakologie   MeSH
• houby účinky léků   MeSH
• lidé MeSH
• multirezistentní tuberkulóza farmakoterapie   MeSH
• Mycobacterium tuberculosis účinky léků   MeSH
• Mycobacterium účinky léků   MeSH
• mykobakteriózy farmakoterapie   MeSH
• mykózy farmakoterapie   MeSH
• tuberkulóza farmakoterapie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH