Synthesis and Antituberculosis Activity of New Hydrazide Derivatives (original) (raw)

Synthesis and Evaluation of Antituberculosis Activity of Substituted 2,7-Dimethylimidazo [1,2-a]Pyridine-3-Carboxamide Derivatives

Open Journal of Medicinal Chemistry, 2016

A series of substituted 2,7-dimethylimidazo[1,2-a]pyridine-3-carboxamides derivatives 5a-5m were synthesized through multi-step reactions. To achieve the synthesis of the desired compounds monobromo and dibromo substituted 2-amino-γ-picoline was reacted with ethyl 2-chloroacetoacetate. The crude ethyl ester subjected to hydrolysis in presence of lithium hydroxide to get 2a and 2b, with imidazo[1,2-a]pyridine-3-carboxylic acid to get 3a-3b, on treatment with substituted amines 4a-4g to get desired product 5a-5m in presence of EDCI and HOBt. The substituted imidazo[1,2-a]pyridine-3-carboxamides are characterized by FTIR, 1 H-NMR, 13 C-NMR and mass spectra. These newly synthesized compounds were tested in vitro for their antimycobacterial activity. The preliminary results of antituberculosis study showed that most of the synthesized compounds 5a-5m demonstrated moderate to good antituberculosis activity. Among the tested compounds 5b, 5d and 5e were found to be the most active with minimum inhibitory concentration (MIC) of 12.5 μg/mL against Mycobacterium tuberculosis (H37 RV strain) ATCC No-27294.

Identification of N‑(2-Phenoxyethyl)imidazo[1,2‑a]pyridine-3- carboxamides as New Antituberculosis Agents

A series of imidazo[1,2-a]pyridine carboxamides (IPAs) bearing an N-(2-phenoxyethyl) moiety was designed and synthesized as new antitubercular agents. Seven 2,6-dimethyl IPAs demonstrated excellent in vitro activity (MIC: 0.025−0.054 μg/mL) against the drug susceptive H37Rv strain and two clinically isolated multidrug-resistant Mycobacterium tuberculosisstrains. Compound 10j displayed acceptable safety and pharmacokinetic properties, opening a new direction for further development. Figure 1. Design of the new molecules.

Synthesis and anti-mycobacterial evaluation of some pyrazine-2-carboxylic acid hydrazide derivatives

European Journal of Medicinal Chemistry, 2010

A series of pyrazine-2-carboxylic acid hydrazide derivatives were synthesized and screened for their activity against Mycobacterium tuberculosis. The results show that pyrazine-2-carboxylic acid hydrazide–hydrazone derivatives 3a–l were less active than pyrazinamide. In contrast, the N4-ethyl-N1-pyrazinoyl-thiosemicarbazide 4 showed the highest activity against M. tuberculosis H37Rv (IC90 = 16.87 μg/mL). Details of the structure–activity and structure–cytotoxicity relationships are discussed.

Synthesis and in vitro antimycobacterial activities of novel 6-substituted-3 (2H)-pyridazinone-2-acetyl-2-(substituted/nonsubstituted acetophenone) hydrazone

Turk. J. …, 2011

The difficulty in managing tuberculosis includes the prolonged duration of the treatment, the emergence of drug resistance, and coinfection with HIV/AIDS. Tuberculosis control requires new drugs that act on novel drug targets to help in combating resistant forms of Mycobacterium tuberculosis and reduce the treatment duration. For this purpose, 6-substituted-3(2 H) -pyridazinone-2-acetyl-2-(substituted/nonsubstituted acetophenone) hydrazone derivatives were synthesized and their structures were elucidated by elemental analyses, IR, and 1 H-NMR. The in vitro antimycobacterial activities of synthesized compounds 5a-l were determined by the agar proportion method against Mycobacterium tuberculosis H37Rv. Among the target compounds, 5b and 5f exhibited the best antimycobacterial activity, with a MIC value of 5 μ g/mL.

Synthesis and antitubercular activity of novel 4-substituted imidazolyl-2, 6-dimethyl-< i> N< sup> 3,< i> N< sup> 5-bisaryl-1, 4-dihydropyridine-3, …

European journal of …, 2009

In the present investigation, a series of 1-isonicotinoyl-3-methyl-4-(2-(substitutedphenyl)hydrazono)-1H-pyrazol-5(H)-ones were synthesized by the reaction between isonicotinohydrazide with substituted ethylacetoacetate derivatives using acetic acid as solvent which yielded substituted pyrazol-5(H)-one derivatives. Newly synthesized compounds were tested for their in vitro anti-tubercular activity against Mycobacterium tuberculosis H37Rv using the BACTEC 460 radiometric system. Among the synthesized compounds, 4-(2-(2,6-dichlorophenyl)hydrazono)-1-isonicotinoyl-3-methyl-1H-pyrazol-5(4H)-one and 4-(2-(1-isonicotinoyl-3-methyl-5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl) benzene-sulfonamide were found to be more active agent against M. tuberculosis H37Rv with minimum inhibitory concentration of 0.0034, 0.0032 µM at actual MIC 1.66 and 1.64 µg/mL, respectively. Isonicotinohydrazide Pyrazol-5(H)-ones Anti-tubercular activity Anti-mycobacterial activity Mycobacterium tuberculosis M. tuberculosis H37Rv

Synthesis and Antimycobacterial Activity of a Novel Series of Isonicotinylhydrazide Derivatives

Archiv der Pharmazie, 2009

A series of eight N'-[(E)-(disubstituted-phenyl)methylidene]isonicotino-hydrazide derivatives were synthesized and evaluated for their in vitro antibacterial activity against Mycobacterium tuberculosis, and the activity expressed as the minimum inhibitory concentration (MIC) in µg/mL. Four compounds 2b-d and 2f exhibited a significant activity (0.6 µg/mL), when compared with first line drugs such as isoniazid (INH) and rifampin (RIP) and could be a good starting point to develop new lead compounds in the fight against multidrug resistant tuberculosis.

Antituberculosis: Synthesis and Antimycobacterial Activity of Novel Benzimidazole Derivatives

BioMed Research International, 2013

A total of seven novel benzimidazoles were synthesized by a 4-step reaction starting from 4-fluoro-3-nitrobenzoic acid under relatively mild reaction conditions. The synthesized compounds were screened for their antimycobacterial activity against M. tuberculosis H 37 Rv (MTB-H 37 Rv) and INH-resistant M. tuberculosis (INHR-MTB) strains using agar dilution method. Three of them displayed good activity with MIC of less than 0.2 M. Compound ethyl 1-(2-(4-(4-(ethoxycarbonyl)-2-aminophenyl)piperazin-1yl)ethyl)-2-(4-(5-(4-fluorophenyl)pyridin-3-ylphenyl-1H-benzo[d]imidazole-5-carboxylate (5g) was found to be the most active with MIC of 0.112 M against MTB-H 37 Rv and 6.12 M against INHR-MTB, respectively.