Journal of the Brazilian Chemical Society
On-line version ISSN 1678-4790
MACEDO, Edângelo M. S. de et al. A new bianthron glycoside as inhibitor of Trypanosoma cruzi glyceraldehyde 3-phosphate dehydrogenase activity. J. Braz. Chem. Soc. [online]. 2009, vol.20, n.5, pp. 947-953. ISSN 1678-4790. http://dx.doi.org/10.1590/S0103-50532009000500021.
A phytochemical investigation of the ethanolic extract of stalks of Senna martiana Benth. (Leguminoseae), native specie of northeast Brazil, resulted in the isolation and spectroscopic characterization of a new bianthrone glycoside, martianine 1 (10,10'-il-chrysophanol-10-oxi10,10'-bi-glucosyl). Its identification was established by HRMS, IR and 2D NMR experiments. The evaluation of martianine trypanocidal activity was carried out against gliceraldehyde 3-phosphate dehydrogenase enzyme from Trypanosoma cruzi. Its inhibitory constant (Ki) is in the low micromolar concentration and it was determined by isothermal titration calorimetry to be 27.3 ± 2.47 µmol L-1. The non-competitive mechanism is asserted to be putative of the mode of action martianine displays against T. cruzi GAPDH. Results show that martianine has a great potential to become new lead molecule by inhibiting this key enzyme and for the development of new drugs against Chagas disease.
Keywords : Senna martiana; Leguminoseae; bianthrone; anthraquinone; Trypanosoma cruzi; isothermal titration calorimetry.