title: Trypanocidal activity of pimarane diterpenes from Viguiera arenaria (Asteraceae).
abstract: Five structurally related pimarane diterpenes isolated from the roots of Viguiera arenaria and a further compound obtained by chemical derivatization were evaluated in vitro against the trypomastigote forms of Trypanosoma cruzi. The natural compound ent-15-pimarene-8 beta,19-diol and the derivative ent-8(14),15-pimaradiene-3beta-acetoxy showed the highest trypanocidal activity, displaying IC(50) values of 116.5 +/- 1.21 and 149.3 +/- 1.07 microM, respectively, while the positive control, violet gentian, showed an IC(50) of 76 microM. Based on the results, it can be concluded that minor structural differences among the tested diterpenes influence significantly the trypanocidal activity, thus bringing new perspectives to the establishment of structure-activity relationships among this type of metabolites to the treatment of Chagas' disease.
authors.affiliation: Universidade de São Paulo (USP), Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Departamento de Química, Ribeirão Preto, SP, Brazil.
authors.forename: Sérgio R
authors.initials: SR
authors.lastname: Ambrósio
authors.forename: Nilton S
authors.initials: NS
authors.lastname: Arakawa
authors.forename: Viviane R
authors.initials: VR
authors.lastname: Esperandim
authors.forename: Sérgio
authors.initials: S
authors.lastname: de Albuquerque
authors.forename: Fernando B
authors.initials: FB
authors.lastname: Da Costa
mesh_terms: D045784:Abietanes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D019659:Asteraceae / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D014344:Trypanocidal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D014349:Trypanosoma cruzi / Q000187:drug effects
chemical_list: D045784:Abietanes; D014344:Trypanocidal Agents; C433018:pimarane