title: Eleutherinone, a novel fungitoxic naphthoquinone from Eleutherine bulbosa (Iridaceae).
abstract: The dichloromethane extract prepared from the underground parts of Eleutherine bulbosa (Miller) Urban (Iridaceae) showed strong activity in the direct bioautography assay with the phytopathogenic fungus Cladosporium sphaerospermum. This assay was used to guide the fractionation of this extract and allowed the isolation of four compounds: the new naphthoquinone eleutherinone[8-methoxy-1-methyl-1,3-dihydro-naphtho(2,3-c)furan-4,9 -dione] and the known compounds, previously isolated from this species, eleutherin [9-methoxy-1(R),3(S)-dimethyl-3,4-dihydro-1H-benzo(g)isochromene-5,10-dione], isoeleutherin [9-methoxy-1(R),3(R)-dimethyl-3,4-dihydro-1H-benzo(g)isochromene-5,10-dione], and eleutherol [4-hydroxy-5-methoxy-3(R)-methyl-3H-naphtho(2,3-c)furan-1 -one]. All quinonoid compounds showed strong antifungal activity in the bioautography assay at 100  g/spot, while eleutherol was inactive.
authors.affiliation: Laboratório de Química de Produtos Naturais, Centro de Pesquisas René Rachou-Fiocruz, Belo Horizonte, MG, Brasil.
authors.forename: Tânia Maria Almeida
authors.initials: TM
authors.lastname: Alves
authors.forename: Helmut
authors.initials: H
authors.lastname: Kloos
authors.forename: Carlos Leomar
authors.initials: CL
authors.lastname: Zani
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000494:pharmacology*; D002963:Cladosporium / Q000187:drug effects*; D027621:Iridaceae / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D009285:Naphthoquinones / Q000737:chemistry / Q000494:pharmacology*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000935:Antifungal Agents; D009285:Naphthoquinones; D010936:Plant Extracts; C478365:eleutherinone