title: Cytotoxic geranylated xanthones and O-alkylated derivatives of alpha-mangostin.
abstract: Two new geranylated xanthones, 6-O-methylcowanin (4) and oliverixanthone (5), along with five known compounds, cowanin, rubraxanthone, cowaxanthone, cowanol, and beta-mangostin, have been isolated from the bark of Garcinia oliveri. For comparison of their biological activities, one mono- and seven di-O-alkylated alpha-mangostin derivatives were synthesized from alpha-mangostin. The structures of all compounds were assigned by spectroscopic methods (1D and 2D NMR and MS). Cytotoxicity of selected xanthones against MCF-7 and DLD-1 cell lines was examined. Evaluation of the structure-activity relationship showed that alpha-mangostin had the strongest activity, and all the O-alkylated alpha-mangostin derivatives showed reduced activity compared to the naturally occurring alpha-mangostin.
authors: Faculty of Chemistry, HCM City University of Natural Sciences, HCM City, Vietnam.
authors: Ly Dieu
authors: LD
authors: Ha
authors: Poul Erik
authors: PE
authors: Hansen
authors: Ole
authors: O
authors: Vang
authors: Fritz
authors: F
authors: Duus
authors: Hung Dinh
authors: HD
authors: Pham
authors: Lien-Hoa Dieu
authors: LH
authors: Nguyen
mesh_terms: D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D029760:Garcinia / Q000737:chemistry; D006801:Humans; D015394:Molecular Structure; D024301:Plant Bark / Q000737:chemistry; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D044004:Xanthones / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity*
chemical_list: D044004:Xanthones; C472155:rubraxanthone; C021053:mangostin