RESUMO
Despite being a curable disease, tuberculosis (TB) remains a public health problem worldwide mainly due to lengthy treatment, as well as its toxic effects, TB/HIV co-infection and the emergence of resistant Mycobacterium tuberculosis strains. These barriers reinforcing the need for development of new antimicrobial agents, that ideally should reduce the time of treatment and be active against susceptible and resistant strains. Quinones are compounds found in natural sources and among them, the naphthoquinones show antifungal, antiparasitic, and antimycobacterial activity. Thus, we evaluated the potential antimycobacterial activity of six 1,4-naphthoquinones derivatives. We determined the minimum inhibitory concentration (MIC) of the compounds against three M. tuberculosis strains: a pan-susceptible H37Rv (ATCC 27294); one mono-resistant to isoniazid (ATCC 35822); and one mono-resistant to rifampicin (ATCC 35838); the cytotoxicity in the J774A.1 (ATCC TIB-67) macrophage lineage; performed in silico analysis about absorption, distribution, metabolism, and excretion (ADME) and docking sites. All evaluated naphthoquinones were active against the three strains with MIC between 206.6 and 12.5 µM, and the compounds with lower MIC values have also showed low cytotoxicity. Moreover, two naphthoquinones derivatives 5 and 6 probably do not exhibit cross resistance with isoniazid and rifampicin, respectively, and regarding ADME analysis, no compound violated the Lipinski's rule-of-five. Considering the set of findings in this study, we conclude that these naphthoquinones could be promising scaffolds to develop new therapeutic strategies to TB.
RESUMO
Several quinonoid and phenazine compounds were synthesized in moderate to high yields and showed activity against H(37)Rv, rifampicin and isoniazid-resistance strains of Mycobacterium tuberculosis. The cytotoxity of the compounds were evaluated against human peripheral blood mononuclear cells (PBMC) and these substances emerge as promising antitubercular prototypes.
Assuntos
Antituberculosos/síntese química , Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Fenazinas/síntese química , Quinonas/síntese química , Antituberculosos/química , Células Cultivadas , Resistência Microbiana a Medicamentos , Isoniazida/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Modelos Moleculares , Fenazinas/química , Fenazinas/farmacologia , Quinonas/química , Quinonas/farmacologia , Rifampina/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Difração de Raios XRESUMO
The reaction of naphthoquinone-oximes (3) and (4) with diazomethane yields directly, in one step, the oxazoles (5) and (6), respectively.
Assuntos
Técnicas de Química Combinatória , Diazometano/química , Naftoquinonas/química , Oxazóis/síntese química , Oximas/química , OxirreduçãoRESUMO
We synthesized new naphthoimidazoles from beta-lapachone with an aromatic moiety linked to the imidazole ring, using phenylic and heterocyclic aldehydes. The most active compound against Trypanosoma cruzi had a p-methyl group linked to the phenyl ring, presenting an EC(50) value of 15.5 +/- 2.9 microM. No reliable correlation could be established with the biological activity and the structure of in the phenylic series. For the heterocyclic series, activity was associated with a three bond-distance from nitrogen to the imidazole ring, in accordance with our previous work.