6537-44-6Relevant articles and documents
Preparation and NMR characterization of new substituted benzo[a]phenazines
Benedetti-Doctorovich, Violeta,Escola, Natalia,Burton, Gerardo
, p. 529 - 532 (1998)
Benzo[a]phenazines were prepared by condensation of β-lapachone with 1,2-phenylenediamme and 4-chloro-1,2-phenylenediamine. The latter diamine gave two regioisomers that could be separated and unambiguously identified by means of their 1H and 13C NMR spectra with the aid of 2D NMR experiments, mainly HETCOR and COLOC.
Antimalarial activity of phenazines from lapachol, β-lapachone and its derivatives against Plasmodium falciparum in vitro and Plasmodium berghei in vivo
De Andrade-Neto, Valter F.,Goulart, Marilia O. F.,Da Silva Filho, Jorge F.,Da Silva, Matuzalem J.,Pinto, Maria Do Carmo F. R.,Pinto, Antonio V.,Zalis, Mariano G.,Carvalho, Luzia H.,Krettli, Antoniana U.
, p. 1145 - 1149 (2004)
The antimalarial activity of benzo[a]phenazines synthesized from 1,2-naphthoquinone, lapachol, β-lapachone and several derivatives have been tested against Plasmodium falciparum in vitro using isolates of parasites with various susceptibilities to chloroquine and/or mefloquine. Parasite growth in the presence of the test drugs was measured by incorporation of [ 3H]-hipoxanthine in comparison to controls with no drugs, always testing in parallel chloroquine, a standard antimalarial. Among seven benzophenazines tested, four had significant in vitro activities; important, the parasites resistant to chloroquine were more susceptible to the active phenazines in vitro. The doses of phenazines causing 50% inhibition of parasite growth varied from 1.67 to 9.44 μM. The two most active ones were also tested in vivo against Plasmodium berghei in mice, in parallel with lapachol and β-lapachone. The 3-sulfonic acid-β-lapachone-derived phenazine was the most active causing up to 98% inhibition of parasitaemia in long term treatment (7 doses) subcutaneouly, whereas the phenazine from 3-bromo-β-lapachone was inactive. Thus, these simple phenazines, containing polar (-Br,-I) and ionizable (-SO3H, -OH) groups, easily synthesized from cheap, natural or synthetic precursors (lapachol and β-lapachone), at rather low cost, provide prototypes for development of new antimalarials aiming the chloroquine resistant parasites.
A macrolactone from benzo[a]phenazine with potent activity against Mycobacterium tuberculosis
Silva, Raphael S.F.,Pinto, Maria do Carmo F.R.,Goulart, Marilia O.F.,de Souza Filho, Jose D.,Neves Jr., Ivan,Lourenco, Maria Cristina S.,Pinto, Antonio V.
scheme or table, p. 2334 - 2337 (2009/09/05)
We report here an alternative to the MCPBA or ozonolysis-based oxidation methods of quinoxaline-featuring compounds prepared from beta-lapachones. The use of peracetic acid allowed a simple preparation of the corresponding macrolactones by cleavage of the ring system. These lactones were evaluated for their antimycobacterial potential and compound 4 turned out to have an MIC of 0.62 μg per mL on Mycocabteriumtuberculosis H37Rv. These results justify further research into its value as a potential lead for an original treatment of tuberculosis.
