title: Cacalolides from Senecio madagascariensis.
abstract: 14-Isovaleryloxy-O-methyl-1,2-dehydrocacalol (1) and cycloart-23-ene-3,25-diol, beta-sitosterol, and stigmasterol, along with five new cacalolides, 1-hydroxy-2-methoxy-1,2,3,4-dehydro-6-dehydroxycacalone (2), 1-hydroxy-2-methoxy-1,2,3,4-dehydrocacalone (3), 1,2-dimethoxy-1,2,3,4-dehydro-6-dehydroxycacalone (4), 1,2-dimethoxy-1,2,3,4-dehydrocacalone (5), and 2-methoxy-O-methyl-1-oxo-2,3-dehydrocacalol (6), were isolated from Senecio madagascariensis collected from Colombia. The structures of the new compounds were determined using one- and two-dimensional NMR techniques. In addition, the structure of 2 was corroborated by derivatizations and single-crystal X-ray diffraction studies.
authors.affiliation: Departamento de Química, Centro de Investigación y de Estudios Avanzados, Instituto Politécnico Nacional, Apartado 14-740, México, D. F. 07000, México.
authors.forename: E
authors.initials: E
authors.lastname: Burgueño-Tapia
authors.forename: M A
authors.initials: MA
authors.lastname: Bucio
authors.forename: A
authors.initials: A
authors.lastname: Rivera
authors.forename: P
authors.initials: P
authors.lastname: Joseph-Nathan
mesh_terms: D019659:Asteraceae / Q000737:chemistry*; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D012717:Sesquiterpenes / Q000737:chemistry / Q000302:isolation & purification*; D016339:Spectrometry, Mass, Fast Atom Bombardment
chemical_list: D012717:Sesquiterpenes