title: Chromenes of polyketide origin from Peperomia villipetiola.
abstract: An extract of leaves and stems of Peperomia villipetiola has been found to contain myristicin (3-methoxy-4,5-methylenedioxy-allylbenzene) and seven chromenes, whose structures are methyl 5-hydroxy-7-methyl-2,2-dimethyl-2H-1-chromene-6-carboxylate (1), methyl 5-methoxy-7-methyl-2,2-dimethyl-2H-1-chromene-8-carboxylate (2), methyl 7-hydroxy-5-methyl-2,2-dimethyl-2H-1-chromene-6-carboxylate (3), methyl 7-methoxy-5-methyl-2,2-dimethyl-2H-1-chromene-6-carboxylate (4), 5-methanol-7-hydroxy-2,2-dimethyl-2H-1-chromene-6-carboxylic acid (5), 5-methanol-7-methoxy-2,2-dimethyl-2H-1-chromene-6-carboxylic acid (6), and methyl 5-acetoxymethanol-7-hydroxy-2,2-dimethyl-2H-1-chromene-6-carboxylate (7). A biosynthetic rationale for 1-7 suggests that orsellinic acid may be a common intermediate. The anti-fungal activities of the chromenes were measured bioautographically against Cladosporium cladosporioides and Cladosporium sphaerospermum: compounds 6 and 7 were found to be the most active.
authors.affiliation: Instituto de Química, Universidade de São Paulo, CP 26077, 05508-900 São Paulo, SP, Brazil.
authors.forename: Karina J
authors.initials: KJ
authors.lastname: Malquichagua Salazar
authors.forename: Guillermo E
authors.initials: GE
authors.lastname: Delgado Paredes
authors.forename: Luis Ripalda
authors.initials: LR
authors.lastname: Lluncor
authors.forename: Maria Claudia Max
authors.initials: MC
authors.lastname: Young
authors.forename: Massuo Jorge
authors.initials: MJ
authors.lastname: Kato
mesh_terms: D001578:Benzopyrans / Q000737:chemistry* / Q000302:isolation & purification; D018942:Macrolides / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008968:Molecular Conformation; D036941:Peperomia / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification; D018515:Plant Leaves / Q000737:chemistry; D018547:Plant Stems / Q000737:chemistry; D013055:Spectrophotometry, Infrared
chemical_list: D001578:Benzopyrans; D018942:Macrolides; D010936:Plant Extracts