Comparative analysis of the trypanocidal activity and chemical properties of E-lychnophoric acid and its derivatives using theoretical calculations

Abstract

E-Lychnophoric acid 1, its derivative ester 2 and alcohol 3 killed 100% of trypomastigote blood forms of Trypanosoma cruzi at the concentrations of 13.86, 5.68, and 6.48 µg/mL, respectively. Conformational distribution calculations (AM1) of 1, 2 and 3 gave minimum energies for the conformers a, b, c, and d, which differ from each other only in the cyclononene ring geometry. Calculations (DFT/BLYP/6-31G*) of geometry optimization and chemical properties were performed for conformers of 1, 2, and 3. The theoretical results were numerically compared to the trypanocidal activity. Calculated values of atomic charge, orbital population, and vibrational frequencies showed that the C-4-C-5 pi-endocyclic bond does not affect the trypanocidal activity of the studied compounds. Nevertheless, the structure of the group at C-4 strongly influences the activity. However, the theoretical results indicated that the intra-ring (C-1 and C-9) and pi-exocycle (C-8 and C-14) carbons of caryophyllene-type structures promote the trypanocidal activity of these compounds.

Evaluation of the bactericidal and trypanocidal activities of triterpenes isolated from the leaves, stems, and flowers of Lychnophora pinaster

“…This species also shows significant antinociceptive and antiinflammatory activities (Guzzo et al, 2008). Rutin, quercetin, isochlorogenic acid, caffeic acid, isovitexin, vitexin, sesquiterpene derivatives (Alcântara et al, 2005;Leite et al, 2008), and the triterpenes lupeol, a mixture of α-and β-amyrin, and friedelin were previously isolated from its aerial parts. Although several studies have lately related triterpenes to treatment of the trypanosomiases (Rosas et al, 2007;Leite et al, 2006;Cunha et al, 2006) and bactericidal activity (Al-Fatimi et al, 2010), no data are available about the trypanocidal and bactericidal activities of triterpenes isolated from Lychnophora species.…”

Caracterização morfológica, perfil químico, atividade biológica e conservação in situ do gênero Lychnophora Mart. (Asteraceae: Vernonieae: Lychnophorinae), Brasil

“…Adaptado de Oliveira et al (1996). Alcântara et al (2005) verificaram que o ácido lychnophorico e seus derivados (éster e álcool) apresentaram 100% de atividade tripanocida nas concentrações de 13,86; 5,68 e 6,48 μg/mL, respectivamente. Segundo os autores, a estrutura do grupo oxigenado influencia o potencial de outros sítios presentes no esqueleto cariofilênico das substâncias, sugerindo que a atividade tripanocida seja promovida pelo sistema π-exocíclico (C-8 e C-14) e pelos átomos de carbono C-1 e C-9.…”

Anti-inflammatory effects in muscle injury by transdermal application of gel with Lychnophora pinaster aerial parts using phonophoresis in rats

“…Species of the genus Lychnophora (Asteraceae) are largely used by the traditional Brazilian medicine for the treatment of various diseases, mainly Chagas and inflammatory diseases [ 1 ]. Lychnophora pinaster Mart, popularly known as “arnica-mineira”, is a native species and widely distributed in the State of Minas Gerais (Brazil).…”