title: Flavonoids from the stem bark of Lonchocarpus xuul.
abstract: The stem bark of Lonchocarpus xuul (Leguminosae) has yielded four flavonoids which have been identified by spectroscopic methods as the novel 4beta,5-dimethoxy-6",6"-dimethyl-2H-pyrano-(2",3":7,6)-fl avan (xuulanin), 3beta,4beta,5-trimethoxy-6",6"-dimethyl-2H-pyrano-(2",3":7,6 )-flavan (3beta-methoxyxuulanin). 4beta-ethoxy-5-methoxy-6",6"-dimethyl-2H-pyrano-(2",3":7,6)- flavan (4beta-demethylxuulanin-4beta-ethyl ether), and the known 5,7-dihydroxy-6,8-di(3-methylbut-2-enyl)flavanone (spiniflavanone-B). The ethyl derivative is considered likely to be an artefact.
authors.affiliation: Grupo de Química Orgánica, Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, A.C., Mérida, Mexico.
authors.forename: R
authors.initials: R
authors.lastname: Borges-Argáez
authors.forename: L M
authors.initials: LM
authors.lastname: Peñia-Rodríguez
authors.forename: P G
authors.initials: PG
authors.lastname: Waterman
mesh_terms: D007887:Fabaceae / Q000737:chemistry*; D005419:Flavonoids / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy; D010946:Plants, Medicinal; D014197:Trees / Q000737:chemistry*
chemical_list: D005419:Flavonoids