title: Dichromenoxanthones from Tovomita brasiliensis.
abstract: Two dichromenoxanthones [1,6-dihydroxy-6',6'-dimethylpyrano(2',3':3,4)-6'',6''-dimethylpyrano(2'',3'':7,8)xanthone (brasilixanthone A) and 1,6-dihydroxy-6',6'-dimethylpyrano(2',3':2,3)-6'',6''-dimethylpyrano(2'',3'':7,8)xanthone (brasilixanthone B)], along with betulinic acid, friedelin, sitosterol and stigmasterol were isolated from the roots and stems of Tovomita brasiliensis. Their structures were characterized on the basis of 1H and 13C NMR spectral data, including 2D NMR experiments.
authors.affiliation: Departamento de Química, Universidade Federal de Alagoas, Maceió, Brazil.
authors.forename: V L
authors.initials: VL
authors.lastname: Marques
authors.forename: F M
authors.initials: FM
authors.lastname: De Oliveira
authors.forename: L M
authors.initials: LM
authors.lastname: Conserva
authors.forename: R G
authors.initials: RG
authors.lastname: Brito
authors.forename: G M
authors.initials: GM
authors.lastname: Guilhon
mesh_terms: D019684:Magnoliopsida / Q000737:chemistry*; D015394:Molecular Structure; D011714:Pyrans / Q000737:chemistry / Q000302:isolation & purification*; D013057:Spectrum Analysis; D014966:Xanthenes / Q000737:chemistry / Q000302:isolation & purification*; D044004:Xanthones
chemical_list: C421810:1,6-dihydroxy-6',6'-dimethylpyrano(2',3':2,3)-6'',6''-dimethylpyrano(2'',3'':7,8)xanthone; C421809:1,6-dihydroxy-6',6'-dimethylpyrano(2',3':3,4)-6'',6''-dimethylpyrano(2'',3'':7,8)xanthone; D011714:Pyrans; D014966:Xanthenes; D044004:Xanthones