title: O-Methylation of phenylphenalenone phytoalexins in Musaacuminata and Wachendorfia thyrsiflora.
abstract: Biosynthetic O-methylation at various sites along the backbone of inducible phenylphenalenones in Musaacuminata var. "Williams" (Musaceae) and Wachendorfiathyrsiflora (Haemodoraceae) was investigated using 13C-labelled precursors. The inducibility of O-methylated metabolites was demonstrated in both species and the origin of methoxyl group from [methyl-13C]L-methionine was confirmed. In addition to known phenylphenalenones, a methoxylated metabolite, 4-(4-hydroxy-3-methoxy-phenyl)-benzo[de]isochromene-1,3-dione, was detected and its structure elucidated mainly by NMR spectroscopic techniques. The experiments were used to discriminate methionine-derived and artificial methoxy groups formed during methanolic extraction. Finally, demethylation of 4'-methoxycinnamic acid and subsequent conversion to 3',4'-methylenedioxycinnamic acid was demonstrated in M.acuminata.
authors: Instituto de Química, Universidad de Antioquia, Calle 67# 53-108, A.A. 1226 Medellín, Colombia.
authors: Felipe
authors: F
authors: Otálvaro
authors: Kusuma
authors: K
authors: Jitsaeng
authors: Tobias
authors: T
authors: Munde
authors: Fernando
authors: F
authors: Echeverri
authors: Winston
authors: W
authors: Quiñones
authors: Bernd
authors: B
authors: Schneider
mesh_terms: D002247:Carbon Isotopes; D019684:Magnoliopsida / Q000737:chemistry / Q000378:metabolism*; D008715:Methionine / Q000378:metabolism*; D008745:Methylation; D015394:Molecular Structure; D028522:Musaceae / Q000737:chemistry / Q000378:metabolism*; D043803:Phenalenes / Q000737:chemistry / Q000378:metabolism*; D012717:Sesquiterpenes / Q000737:chemistry / Q000378:metabolism*; D000094162:Phytoalexins
chemical_list: D002247:Carbon Isotopes; D043803:Phenalenes; D012717:Sesquiterpenes; D008715:Methionine; D000094162:Phytoalexins