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1.
Curr Issues Mol Biol ; 46(7): 6489-6507, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39057029

RESUMO

Tuberculosis is a highly lethal bacterial disease worldwide caused by Mycobacterium tuberculosis (Mtb). Caespitate is a phytochemical isolated from Helichrysum caespititium, a plant used in African traditional medicine that shows anti-tubercular activity, but its mode of action remains unknown. It is suggested that there are four potential targets in Mtb, specifically in the H37Rv strain: InhA, MabA, and UGM, enzymes involved in the formation of Mtb's cell wall, and PanK, which plays a role in cell growth. Two caespitate conformational structures from DFT conformational analysis in the gas phase (GC) and in solution with DMSO (CS) were selected. Molecular docking calculations, MM/GBSA analysis, and ADME parameter evaluations were performed. The docking results suggest that CS is the preferred caespitate conformation when interacting with PanK and UGM. In both cases, the two intramolecular hydrogen bonds characteristic of caespitate's molecular structure were maintained to achieve the most stable complexes. The MM/GBSA study confirmed that PanK/caespitate and UGM/caespitate were the most stable complexes. Caespitate showed favorable pharmacokinetic characteristics, suggesting rapid absorption, permeability, and high bioavailability. Additionally, it is proposed that caespitate may exhibit antibacterial and antimonial activity. This research lays the foundation for the design of anti-tuberculosis drugs from natural sources, especially by identifying potential drug targets in Mtb.

2.
Int J Mol Sci ; 24(20)2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37895100

RESUMO

A variety of ribo-, 2'-deoxyribo-, and 5'-norcarbocyclic derivatives of the 8-aza-7-deazahypoxanthine fleximer scaffolds were designed, synthesized, and screened for antibacterial activity. Both chemical and chemoenzymatic methods of synthesis for the 8-aza-7-deazainosine fleximers were compared. In the case of the 8-aza-7-deazahypoxanthine fleximer, the transglycosylation reaction proceeded with the formation of side products. In the case of the protected fleximer base, 1-(4-benzyloxypyrimidin-5-yl)pyrazole, the reaction proceeded selectively with formation of only one product. However, both synthetic routes to realize the fleximer ribonucleoside (3) worked with equal efficiency. The new compounds, as well as some 8-aza-7-deazapurine nucleosides synthesized previously, were studied against Gram-positive and Gram-negative bacteria and M. tuberculosis. It was shown that 1-(ß-D-ribofuranosyl)-4-(2-aminopyridin-3-yl)pyrazole (19) and 1-(2',3',4'-trihydroxycyclopent-1'-yl)-4-(pyrimidin-4(3H)-on-5-yl)pyrazole (9) were able to inhibit the growth of M. smegmatis mc2 155 by 99% at concentrations (MIC99) of 50 and 13 µg/mL, respectively. Antimycobacterial activities were revealed for 4-(4-aminopyridin-3-yl)-1H-pyrazol (10) and 1-(4'-hydroxy-2'-cyclopenten-1'-yl)-4-(4-benzyloxypyrimidin-5-yl)pyrazole (6). At concentrations (MIC99) of 40 and 20 µg/mL, respectively, the compounds resulted in 99% inhibition of M. tuberculosis growth.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Nucleosídeos/farmacologia , Nucleosídeos/química , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Pirazóis/farmacologia , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade
3.
Antimicrob Agents Chemother ; 65(11): e0097421, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-34398674

RESUMO

In this work, we assess antituberculosis activity of OTB-658 in vitro and in vivo. In vitro, OTB-658 showed bacteriostatic effectiveness with a lower MIC than linezolid against Mycobacterium tuberculosis. The minimal bactericidal concentrations and time-kill curves for OTB-658 indicated inhibition activity similar to that of linezolid. OTB-658 entered macrophages to inhibit M. tuberculosis growth. OTB-658 had a low mutation frequency (10-8), which would prevent drug-resistant mutations from emerging in combination regimens. In vivo, OTB-658 reduced CFU counts in the lungs and slightly inhibited bacterial growth in the spleen in the early stage and steady state in acute and chronic murine TB models. These results support the preclinical evaluation of OTB-658 and further clinical trials in China.


Assuntos
Mycobacterium tuberculosis , Oxazolidinonas , Animais , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Linezolida/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Oxazolidinonas/farmacologia
4.
Bioorg Med Chem Lett ; 48: 128261, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34265421

RESUMO

We herein report new 5-substituted uridine derivatives as potent inhibitors of mycobacteria - causative agents of tuberculosis. A series of new 5-alkynyl-substituted uridine derivatives were synthesised via palladium-catalysed Sonogashira cross-coupling reaction of 5-iodo-6-methylpyrimidine base with terminal acetylenes with good yields in DMF at room temperature. It was found that methyl group in C-6 position of pyrimidine ring had no impact on yields of target compounds. All obtained compounds were evaluated for their antimycobacterial activity against Mycobacetrium bovis and Mycobacterium tuberculosis at concentrations of 1-100 µg/ml using MABA test. Synthesized nucleosides showed high antimycobacterial activity against M. bovis and M. Tuberculosis. The MIC50 values of 11 and 13 were similar or close to that of the reference drug rifampicin.


Assuntos
Antituberculosos/farmacologia , Desenho de Fármacos , Mycobacterium bovis/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Nucleosídeos de Pirimidina/farmacologia , Antituberculosos/síntese química , Antituberculosos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Nucleosídeos de Pirimidina/síntese química , Nucleosídeos de Pirimidina/química , Relação Estrutura-Atividade
5.
Bioorg Med Chem Lett ; 30(16): 127351, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32631549

RESUMO

A series of new 5-alkynyl-substituted uracil and uridine derivatives were synthesised via palladium-catalysed Sonogashira cross-coupling reaction of 5-bromo-pyrimidine base with terminal acetylenes with good yields in DMF at room temperature. All obtained compounds were tested for antimycobacterial activity against Mycobacetrium bovis and Mycobacterium tuberculosis (H37Ra) at concentrations of 1-100 µg/ml using MABA test. Obtained results revealed that most of tested uracil derivatives exhibited high antimycobacterial activity (MIC50 = 1.1-19.2 µg/ml) in comparison with therapeutic agents such as rifampicin, isoniazid and d-cycloserine, excluding compounds having alkyl substituent at triple alkyne bond.


Assuntos
Antituberculosos/farmacologia , Mycobacterium bovis/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Uracila/farmacologia , Antituberculosos/síntese química , Antituberculosos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Uracila/análogos & derivados , Uracila/química
6.
Arch Pharm (Weinheim) ; 353(7): e1900368, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32399980

RESUMO

Rationally designed Mycobacterium tuberculosis (Mtb) inhibitors were synthesized under Buchwald conditions using Pd2 (dba)3 /xantphos and the compounds were investigated for their biological activity against the Mtb standard strain H37Rv and two other clinically isolated multidrug-resistant strains with different drug resistance patterns. Compounds 5e, 6e, 7e, and 8e exhibited excellent antituberculosis activity against H37Rv with a minimum inhibitory concentration (MIC) value of 15 µg/ml. Compounds 5a, 6c, 7b, 8a, 8b, and 8d also displayed their potency with a MIC value in the range of 15-25 µg/ml. In addition to the Mtb studies, compounds 4e, 5e, 7e, and 8e were tested for cytotoxicity on HEK-293 cells and compounds 7e and 8e were identified to have low toxicities of up to 200 and 300 µM, respectively. The synthesized compounds docked with the 2FUM protein of Mtb and the docking studies revealed that compounds 5e, 6e, 7e, and 8e can bind strongly in the active site of the enzyme and showed binding energies of -9.62, -10.7, -11.48, and -12.06 kcal/mol, respectively. Compound 7e forms four hydrogen bonds, whereas compound 8e forms five hydrogen bonds with amino acids, respectively. Based on these results, compounds 7e and 8e might be considered potential lead compounds with good anti-Mtb potency.


Assuntos
Antituberculosos/farmacologia , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Pirazinas/farmacologia , Antituberculosos/síntese química , Antituberculosos/química , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Estrutura Molecular , Pirazinas/síntese química , Pirazinas/química , Relação Estrutura-Atividade
7.
Bioorg Med Chem Lett ; 29(11): 1363-1369, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30935794

RESUMO

Polyaniline (PANI) and its drug composites with some drugs like Neomycin (NM), Trimethoprim (TMP) and Streptomycin (ST) have been prepared by oxidative polymerization of aniline using hydrochloric acid (HA) and ammonium persulfate (APS) as a dopant and as an oxidant, respectively. The structures of PANI and PANI-drug composites were elucidated by FTIR and NMR spectroscopy, which confirmed the presence of benzenoid and quinoid rings in the synthesized compound. Molecular weight and thermal stability were determined by gel permeation chromatography (GPC) and thermogarvimetric analysis, respectively. From the GPC, PDI values of PANI-NM, PANI-TMP and PANI-ST were found to be 1.37, 1.23 and 1.56, respectively. For the study of antibacterial behavior of the synthesized PANI and PANI-drug composites, different micro-organisms, namely, four Gram positive (S. aureus MTCC 96, B. subtilis MTCC 441, S. pyogenes MTCC 442 and S. mutans MTCC 890) and four Gram negative (S. typhi MTCC 98, KL. pneumoniae MTCC 109, E. coli MTCC 443 and P. aeruginosa MTCC 1688) bacteria were selected due to their pharmacological importance. Some of the PANI-drug composites were found to show excellent results as compared to components polyaniline and drugs used for composite formation. Antituberculosis activity of the PANI and its drug composites against Mycobacterium tuberculosisH37RV (acid fast Bacilli) was determined. MIC values for PANI-NM and PANI-TMP were found to be 0.12 and 0.20 µg/mL, respectively. Results suggested that some of the drug composites may be tried as potential candidates for use as an antituberculoid agent to reduce TB transmission.


Assuntos
Compostos de Anilina/farmacologia , Antituberculosos/farmacologia , Neomicina/farmacologia , Estreptomicina/farmacologia , Trimetoprima/farmacologia , Tuberculose/tratamento farmacológico , Compostos de Anilina/química , Antituberculosos/síntese química , Antituberculosos/química , Relação Dose-Resposta a Droga , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Neomicina/química , Estreptomicina/química , Relação Estrutura-Atividade , Trimetoprima/química
8.
Arch Pharm (Weinheim) ; 352(1): e1800248, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30521146

RESUMO

Aromatic heterocycles with basic nitrogen atoms as well as carboxylic acid derivatives are the dominating chemical space in the universe of drug-like molecules. These established and exceedingly evaluated structural motifs have to be combined with elements of diversity in order to chart less well-explored galaxies of chemical space and to be able to tackle seemingly undruggable targets. Flat scaffolds should be replaced by shapely molecular cores. In this context, it has been unheeded that phenyl rings in diaryl sulfides are less co-planar than in ethers and that the metabolic interconnection of sulfides and sulfoxides offers advantages that are unalike from the chemistry of amines and N-oxides in the CHN-O world. Moreover, σ-hole potentials increase with the polarizability of the atom N < P < O < S and do not only play a role in long-time overlooked halogen bonds. Examples for λ2 , λ4 , and λ6 S-based functionalities related to improved solubility, reduced drug resistance, linkers in drug conjugates, drug-targeting to parasites, and as basis for drug monitoring in sports are given and discussed.


Assuntos
Sulfetos/química , Sulfóxidos/química , Química Farmacêutica , Modelos Moleculares , Estrutura Molecular , Oxirredução , Sulfetos/farmacologia , Sulfóxidos/farmacologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-29987141

RESUMO

The increasing incidence of multidrug-resistant Mycobacterium tuberculosis strains and the very few drugs available for treatment are promoting the discovery and development of new molecules that could help in the control of this disease. Bacteriocin AS-48 is an antibacterial peptide produced by Enterococcus faecalis and is active against several Gram-positive bacteria. We have found that AS-48 was active against Mycobacterium tuberculosis, including H37Rv and other reference and clinical strains, and also against some nontuberculous clinical mycobacterial species. The combination of AS-48 with either lysozyme or ethambutol (commonly used in the treatment of drug-susceptible tuberculosis) increased the antituberculosis action of AS-48, showing a synergic interaction. Under these conditions, AS-48 exhibits a MIC close to some MICs of the first-line antituberculosis agents. The inhibitory activity of AS-48 and its synergistic combination with ethambutol were also observed on M. tuberculosis-infected macrophages. Finally, AS-48 did not show any cytotoxicity against THP-1, MHS, and J774.2 macrophage cell lines at concentrations close to its MIC. In summary, bacteriocin AS-48 has interesting antimycobacterial activity in vitro and low cytotoxicity, so further studies in vivo will contribute to its development as a potential additional drug for antituberculosis therapy.


Assuntos
Antituberculosos/farmacologia , Bacteriocinas/farmacologia , Etambutol/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Animais , Linhagem Celular , Sinergismo Farmacológico , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Testes de Sensibilidade Microbiana/métodos , Muramidase/metabolismo , Células RAW 264.7 , Tuberculose/metabolismo
10.
BMC Complement Altern Med ; 18(1): 5, 2018 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-29310671

RESUMO

BACKGROUND: Costus speciosus, Cymbopogon citratus, and Tabernaemontana coronaria are herbal plants traditionally used as remedies for symptoms of tuberculosis (TB) including cough. The aims of the present study were to evaluate the in vitro anti-TB activity of different solvent partitions of these plants, to identify the phytochemical compounds, and to assess the effects of the most active partitions on the growth kinetics and cellular integrity of the tubercle organism. METHODS: The in vitro anti-TB activity of different solvent partitions of the plant materials was determined against M. tuberculosis H37Rv using a tetrazolium colorimetric microdilution assay. The phytochemical compounds in the most active partition of each plant were identified using gas chromatography-mass spectrometry (GC-MS) analysis. The effects of these partitions on the growth kinetics of the mycobacteria were evaluated over 7-day treatment period in a batch culture system. Their effects on the mycobacterial cellular integrity were observed under a scanning electron microscope (SEM). RESULTS: The respective n-hexane partition of C. speciosus, C. citratus, and T. coronaria exhibited the highest anti-TB activity with minimum inhibitory concentrations (MICs) of 100-200 µg/mL and minimum bactericidal concentration (MBC) of 200 µg/mL. GC-MS phytochemical analysis of these active partitions revealed that majority of the identified compounds belonged to lipophilic fatty acid groups. The active partitions of C. speciosus and T. coronaria exhibited high cidal activity in relation to time, killing more than 99% of the cell population. SEM observations showed that these active plant partitions caused multiple structural changes indicating massive cellular damages. CONCLUSIONS: The n-hexane partition of the plant materials exhibited promising in vitro anti-TB activity against M. tuberculosis H37Rv. Their anti-TB activity was supported by their destructive effects on the integrity of the mycobacterial cellular structure.


Assuntos
Antituberculosos/farmacologia , Costus/química , Mycobacterium tuberculosis/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tabernaemontana/química , Antituberculosos/química , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Extratos Vegetais/química
11.
Arch Pharm (Weinheim) ; 350(9)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28752666

RESUMO

Twenty-three known unsaturated and fused Mannich ketones and their reduced derivatives (amino alcohols) were selected for an antituberculotic study. They were screened against several mycobacterial strains including Mycobacterium tuberculosis, M. xenopi, and M. gordonae, and minimum inhibitory concentration values were also determined using the standard antituberculotic drug isoniazid (INH) as a reference. Structure-activity relationships were also studied. The mode of action of the test compounds was investigated using transmission electron microscopy, high-performance liquid chromatography, and matrix-assisted desorption/ionization mass spectrometry. Several test substances proved to be as potent as INH, but their antimycobacterial spectra were broader than that of INH. Our findings suggest that their mode of action is probably through the inhibition of mycobacterial cell wall biosynthesis.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Cetonas/síntese química , Cetonas/farmacologia , Bases de Mannich/síntese química , Bases de Mannich/farmacologia , Mycobacterium/efeitos dos fármacos , Antituberculosos/síntese química , Antituberculosos/farmacologia , Isoniazida/farmacologia , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Relação Estrutura-Atividade
12.
Arch Pharm (Weinheim) ; 349(11): 817-826, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27775177

RESUMO

Mycobacterium tuberculosis enoyl-ACP reductase (InhA) has been validated as a promising target for antitubercular agents. Isoniazid (INH), the most prescribed drug to treat tuberculosis (TB), inhibits a NADH-dependent InhA that provides precursors of mycolic acids, which are components of the mycobacterial cell wall. It is a pro-drug that needs activation to form the inhibitory INH-NAD adduct by KatG coding for catalase-peroxidase. The INH resistance of M. tuberculosis is caused by mutations in KatG, which may lead to multidrug-resistant TB (MDR-TB). Hence, there is a need for new drugs that can combat MDR-TB. The rationale for the development of new drugs to combat MDR-TB strains is the design of InhA inhibitors that can bypass bioactivation by KatG. In the present review, special attention was paid to discuss the chemical nature and recent developments of direct InhA inhibitors. The InhA inhibitors reported here have significant inhibitory effects against Mtb InhA. The diphenyl ether derivatives have shown slow onset, a tight-binding mechanism, and high affinity at the InhA active site. However, some of the diphenyl ethers have significant in vitro efficacy, which fails to transform into in vivo efficacy. Among the InhA inhibitors, 4-hydroxy-2-pyridones have emerged as a new chemical class with significant InhA inhibitory activity and better pharmacokinetic parameters when compared to diphenyl ethers.


Assuntos
Antituberculosos/química , Antituberculosos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/enzimologia , Oxirredutases/antagonistas & inibidores , Amidas/química , Amidas/farmacologia , Simulação de Dinâmica Molecular , Éteres Fenílicos/química , Éteres Fenílicos/farmacologia , Piranos/química , Piranos/farmacologia , Piridonas/química , Piridonas/farmacologia , Pirrolidinas/química , Pirrolidinas/farmacologia
13.
Bioorg Med Chem Lett ; 25(3): 524-8, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25556103

RESUMO

The Petasis reaction of 6-hydroxy adducts of 1-alkyl-2,3-dicyano-5-arylpyrazinium salts with trans-styrylboronic acids proved to proceed smoothly at room temperature to give the corresponding 5-(hetero)aryl-6-styryl substituted 1,6-dihydropyrazine derivatives. Also it has been found that C(6) unsubstituted 1,6-dihydro- or 1,4,5,6-tetrahydropyrazine derivatives can be easy prepared in high yields from the corresponding pyrazinium salts by reduction with triethylsilane. All synthesized compounds were screened in vitro for their antifungal activities against seven pathogenic fungal strains and antimycobacterial activities against Mycobacterium tuberculosis H37Rv, avium, terrae and multi-drug-resistant strains isolated from tuberculosis patients in the Ural region (Russia).


Assuntos
Antifúngicos/síntese química , Antituberculosos/síntese química , Nitrilas/química , Pirazinas/química , Antifúngicos/química , Antifúngicos/farmacologia , Antituberculosos/química , Antituberculosos/farmacologia , Cristalografia por Raios X , Farmacorresistência Bacteriana/efeitos dos fármacos , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Conformação Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Nitrilas/síntese química , Nitrilas/farmacologia , Oxirredução , Pirazinamida/síntese química , Pirazinamida/química , Pirazinamida/farmacologia , Pirazinas/síntese química , Pirazinas/farmacologia , Silanos/química , Estereoisomerismo , Relação Estrutura-Atividade
15.
Polym Bull (Berl) ; : 1-21, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37362957

RESUMO

The preparation of polyaniline (PANI) and its copolymer with indole involved a chemical oxidative polymerization method, with benzene sulfonic acid (BSA, C6H6O3S) used as a dopant and potassium persulfate (PPS, K2S2O8) as an oxidant. The synthesized compounds underwent characterization using FTIR, 1H-NMR, TGA, and GPC techniques, which allowed the calculation of their average molecular weight and polydispersity index (PDI) through the GPC technique. The PDI values of the PANI copolymer with indole in different aniline-to-indole ratios were 1.53, 1.13, and 1.532 for 1:1, 1:2, and 2:1 ratios, respectively. Thermal stability was determined using TGA, revealing that the indole heterocyclic compound increased the inflexibility of the polymer chains in the synthesized PANI copolymer. The structure of the copolymer was further analyzed using 1HNMR and FTIR techniques, which confirmed the existence of benzenoid and quinoid groups in the PANI-indole copolymers, as well as the effect of doping on the polymer chains. The antibacterial and antifungal properties of the copolymers were studied against several bacterial and fungal strains and measured in terms of minimum inhibitory concentration. Results indicated that the inhibition rate of the PANI-indole copolymer on S. pyogenus (MTCC 442) was higher than that of standard drugs and individual PANI. The PANI-indole copolymers also displayed excellent antituberculosis and antimalarial activities, with the synthesized copolymer showing better outcomes than individual PANI.

16.
Curr Comput Aided Drug Des ; 17(2): 294-306, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32141422

RESUMO

Tuberculosis (TB) is a major cause of mortality and illness as reported by the W.H.O in 2019. The WHO report also mentioned the fact that about 10.0 million people fell ill with tuberculosis in the year 2018. Hydrazide-hydrazones having azomethine group (-NH-N=CH-) connected with carbonyl group is reported for the number of bioactivities like anti-inflammatory, anticonvulsant, anticancer, antiviral and antiprotozoal. OBJECTIVE: The objective of our current study is to design and synthesise more potent hydrazide- hydrazones, containing anti-tubercular agents. METHODS: In the current study, we synthesized 10 hydrazones (3a-3j) by stirring corresponding benzohydrazides (2) with substituted aldehydes (1a-j) in ethanol as a solvent and acetic acid as a catalyst at room temperature. All synthesized compounds were characterized by various spectroscopic techniques including elemental analysis, ultraviolet-visible spectroscopy, fluorescence, fourier- transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. Compounds (3a-3j) were tested for in vitro anti-TB activity using Microplate Alamar Blue Assay (MABA). RESULTS: All our synthesized compounds (3a-3j) were found to be potent against Mycobacteria tuberculosis (H37RV strain) with MIC (minimum inhibitory concentrations) values of 3.125-50 µg/mL. The hydrazide CO-NH protons in (3a-j) compounds are highly deshielded and showed broad singlet at 9.520-9.168 ppm. All the compounds were found to have more intense emission in the 416 - 429 nm regions and strong absorption in the regions of 316 - 327 nm. Synthesized compounds were also tested for in silico analysis using different software for their Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) analysis. All the compounds were found to be in silico non-carcinogenic. CONCLUSION: It will be worth saying that our in silico and in vitro approaches used in the current study will become a guide for medicinal chemists to make structural modifications and synthesize more effective and potent hydrazone containing anti-tubercular agents.


Assuntos
Antituberculosos/síntese química , Antituberculosos/farmacologia , Simulação por Computador , Hidrazonas/síntese química , Hidrazonas/farmacologia , Células CACO-2 , Humanos , Testes de Sensibilidade Microbiana/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/fisiologia , Relação Estrutura-Atividade
17.
Comb Chem High Throughput Screen ; 23(5): 392-401, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32209038

RESUMO

BACKGROUND: Since the last few decades, the healthcare sector is facing the problem of the development of multidrug-resistant (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) infections all over the world. Regardless of the current healthcare progress for the treatment of mycobacterial infections, we are still unable to control addition of every year 9 million new cases of tuberculosis (TB). OBJECTIVE: We had an objective to synthesize some novel hydrazones, which were further subjected to characterization, Photoluminescence study, in vitro anti-mycobacterium testing and in silico ADMET predictions. METHODS: Some new hydrazone derivatives have been successfully prepared by the condensation reaction in the present study. All the compounds were characterized by using FTIR, NMR, UV, Fluorescence spectroscopic techniques. RESULTS: All our newly synthesized compounds showed strong electronic excitation at 292.6 - 319.0 nm and displayed more intense emissions in the 348 - 365 nm regions except compound 3i. The newly synthesized hydrazones 3a, 3b, 3f and 3g were found to be the most active compounds and showed MIC (Minimum inhibitory concentrations) values of 12.5 µg/mL. CONCLUSION: In the realm of development of more potent, effective, safer and less toxic antituberculosis agents; our current study would definitely help the medicinal chemists to develop potent analogues containing hydrazine motifs in them.


Assuntos
Antituberculosos/farmacologia , Hidrazonas/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Antituberculosos/síntese química , Antituberculosos/química , Relação Dose-Resposta a Droga , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Tuberculose/microbiologia
18.
J Glob Antimicrob Resist ; 22: 57-62, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31809940

RESUMO

OBJECTIVES: Tuberculosis (TB) poses a serious global threat to humans. New bactericidal agents that can shorten treatment duration and target drug resistance still remain a top priority in the discovery of anti-TB drugs. The objective of this study was to investigate the bactericidal potential of 3-cinnamoyl-4-hydroxy-6-methyl-2-pyrone (CHP) against drug-susceptible, drug-resistant clinical isolates and drug-tolerant Mycobacterium tuberculosis. METHODS: The minimum bactericidal concentration (MBC) was determined by colony-forming unit (CFU) enumeration. The kill curve analysis was done at different concentrations spanning over 16 days. Drug combination studies with antituberculosis drugs were done to investigate possible synergy. The potential against drug- resistant isolates of M. tuberculosis was done by broth dilution assay. CFU enumeration was done to determine its activity against nutrient-starved drug tolerants, and its feasibility for oral administration was tested by serum inhibitory titre. RESULTS: CHP displayed bactericidal activity with an MBC of 4 µg/mL against M. tuberculosis H37Rv. The kill curve analysis exhibited a biphasic pattern of killing. CHP showed synergy with rifampicin, isoniazid and amikacin but was indifferent towards ethambutol and levofloxacin. CHP retained its full activity against drug-susceptible, monoresistant and multidrug-resistant (MDR) clinical isolates. CHP showed very strong bactericidal activity against nondividing, drug-tolerant M. tuberculosis that on comparison was highly superior to rifampicin. Furthermore, CHP significantly improved the bactericidal activity of rifampicin and isoniazid in a combination study. The serum inhibitory titre in mice indicated its high oral bioavailability. CONCLUSION: Our results show strong bactericidal potential of CHP against M. tuberculosis that warrant its immediate mechanistic, pharmacokinetic and pharmacodynamic studies.


Assuntos
Mycobacterium tuberculosis , Preparações Farmacêuticas , Animais , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Camundongos , Testes de Sensibilidade Microbiana , Pironas
19.
Chem Biol Drug Des ; 96(6): 1362-1371, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32515129

RESUMO

Tuberculosis (TB) is a highly infectious disease that has been plaguing the human race for centuries. The emergence of multidrug-resistant strains of TB has been detrimental to the fight against tuberculosis with very few safe therapeutic options available. As part of an ongoing effort to identify potent anti-tuberculosis agents, we synthesized and screened a series of novel imidazo[1,2-a]pyridinecarboxamide derivatives for their anti-tuberculosis properties. These compounds were designed based on reported anti-tuberculosis properties of the indolecarboxamides (I2Cs) and imidazo[1,2-a]pyridinecarboxamides (IPAs). In this series, we identified compounds 15 and 16 with excellent anti-TB activity against H37Rv strain of tuberculosis (MIC = 0.10-0.19 µM); these compounds were further screened against selected clinical isolates of Mtb. Compounds 15 and 16 showed excellent activities against multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of TB (MIC range: 0.05-1.5 µM) with excellent selectivity indices. In addition, preliminary ADME studies on compound 16 showed favorable pharmacokinetic properties.


Assuntos
Antituberculosos/farmacologia , Desenho de Fármacos , Piridinas/química , Piridinas/farmacologia , Antituberculosos/síntese química , Antituberculosos/farmacocinética , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/efeitos dos fármacos , Piridinas/síntese química , Piridinas/farmacocinética , Análise Espectral/métodos , Relação Estrutura-Atividade
20.
Iran J Pharm Res ; 18(2): 860-866, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531068

RESUMO

Tuberculosis (TB) is a leading cause of death worldwide from infectious diseases and its inadequate treatment has led to emergence of resistant strains. The emergence of these strains renders the search for new drugs for the treatment of TB. The aim of this study was the evaluation of the anti-TB activity of the extract from fungus Gliocladium sp. MR41, and bioassay-guided fractionation and identification of majority compounds was carried out. Fungal strain culture was lyophilized and extracted by maceration in Ethyl Acetate (EtOAc). This extract was fractionated by liquid-liquid partitioning and chromatographic techniques, and the compounds were identified by their spectroscopic data. Furthermore, the EtOAc extract, fractions, and pure compounds were tested on Mycobacterium tuberculosis using the Microplate Alamar Blue Assay. From the bioactive AcetoNitrile Fraction (AcNF; MIC = 3.13 µg/mL) of the EtOAc extract, four compounds were isolated: ergosterol (1), ergosterol-5, 8-peroxide (2), 1, 6-di-O-acetyl-2,3,4,5-tetrahydroxy-hexane (3), and allitol (4). Only 2 exhibited potent activities against M. tuberculosis (MIC = 0.78 µg/mL). Additionally, this is the first report, to our knowledge, of polyols 3 and 4 from this fungus.

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