Leaf-Cutting Ants Toxicity of Limonexic Acid and Degraded Limonoids from Raulinoa echinata. X-Ray Structure of Epoxy-fraxinellone
نویسندگان
چکیده
A investigação fitoquímica das raízes de Raulinoa echinata, planta endêmica do Vale do Itajaí/ SC, levou ao isolamento e identificação dos limonóides degradados: fraxinelona, fraxinelonona e epoxi-fraxinelona. O último foi anteriormente isolado dos caules, porém sua configuração relativa não foi resolvida por experimentos de RMN. Este trabalho apresenta a análise de difração de raios-X da epoxi-fraxinelona, descreve o isolamento da fraxinelonona e fraxinelona pela primeira vez em Raulinoa, e a atividade tóxica da primeira sobre formigas cortadeiras (Atta sexdens rubropilosa). Pouca atividade foi observada para o limonóide degradado testado; entretanto, o limonóide ácido limonéxico isolado dos caules, apresentou alta toxicidade contra as formigas cortadeiras, reduzindo consideravelmente a longevidade das mesmas, em comparação com o controle.
منابع مشابه
Limonoids from the endemic Brazilian species Raulinoa echinata.
Phytochemical survey of stems and leaves of the South Brazilian endemic Raulinoa echinata Cowan, Rutaceae led to the isolation of five limonoid derivatives: the widespread limonin, limonexic acid, kihadalactone B, a methoxylated limonexic acid derivative and a degraded limonoid structurally related to fraxinellone. The two latter compounds have been isolated for the first time. These compounds ...
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