RESUMO
Three new prenylated anthranoids, harunmadagascarins C (1) and D (2) and kenganthranol D (3), together with three known compounds (4-6) were isolated from the leaves of Harungana madagascariensis. Their structures were assigned by spectroscopic methods and by comparison with literature data. In the three new natural products 1-3, one or two prenyl groups are incorporated in furan, pyran, or cyclohexane rings in four different modes of annulation. Compounds 2, 4, and 6 were strongly active against the Gram-positive Bacillus megaterium.
Assuntos
Antracenos/isolamento & purificação , Antracenos/farmacologia , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Clusiaceae/química , Plantas Medicinais/química , Antracenos/química , Antibacterianos/química , Bacillus megaterium/efeitos dos fármacos , Camarões , Testes de Sensibilidade Microbiana , Estrutura Molecular , Folhas de Planta/químicaRESUMO
One new prenylated 1,4-anthraquinone and three new prenylated anthranols, named kengaquinone (1) and kenganthranols A (2), B (3), and C (4), were isolated from a hexane extract of the stem bark of Harungana madagascariensis. Six known compounds including anthraquinones, anthrones, and xanthones were also isolated and identified. The structures of the new compounds were determined by analysis of spectroscopic data and comparison with data of previously known analogues. Some isolated compounds (3-5, 7-11) were evaluated for their alpha-glucosidase inhibition activity. Compounds 3, 4, 8, and 11 showed significant activity, whereas compounds 7, 9, and 10 were inactive in this test.