title: seco-iridoids from Calycophyllum spruceanum (Rubiaceae).
abstract: Three seco-iridoids 7-methoxydiderroside, 6'-O-acetyldiderroside and 8-O-tigloyldiderroside, were isolated from the wood bark of Calycophyllum spruceanum together with the known iridoids loganetin, loganin and the seco-iridoids secoxyloganin, kingiside and diderroside. Their structures were elucidated by means of NMR and MS spectral data analysis. Using NOE correlations and coupling constants, the relative stereochemistry of the new derivatives was established. 7-Methoxydiderroside, 6'-O-acetyldiderroside and the known secoxyloganin and diderroside showed in vitro activity against trypomastigote forms of Trypanosoma cruzi, with IC(50) values of 59.0, 90.2, 74,2 and 84.9 microg/mL, respectively and were compared to the standard gentian violet (IC(50) 7.5 microg/ml).
authors.affiliation: NuBBE-Núcleo de Bioensaios, Biossíntesse e Ecofisiologia de Produtos Naturais, Instituto de Química, Universidade Estadual Paulista, CP 355, CEP 14801-970, Araraquara, São Paulo, Brazil.
authors.forename: Luz Margarita
authors.initials: LM
authors.lastname: Cardona Zuleta
authors.forename: Alberto José
authors.initials: AJ
authors.lastname: Cavalheiro
authors.forename: Dulce Helena
authors.initials: DH
authors.lastname: Siqueira Silva
authors.forename: Maysa
authors.initials: M
authors.lastname: Furlan
authors.forename: Maria Claudia
authors.initials: MC
authors.lastname: Marx Young
authors.forename: Sérgio
authors.initials: S
authors.lastname: Albuquerque
authors.forename: Ian
authors.initials: I
authors.lastname: Castro-Gamboa
authors.forename: Vanderlan
authors.initials: V
authors.lastname: da Silva Bolzani
mesh_terms: D000818:Animals; D005960:Glucosides / Q000737:chemistry / Q000302:isolation & purification; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification; D057888:Iridoid Glucosides; D039823:Iridoids / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D019666:Rubiaceae / Q000737:chemistry*; D013237:Stereoisomerism; D014344:Trypanocidal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D014349:Trypanosoma cruzi / Q000187:drug effects / Q000235:genetics
chemical_list: D005960:Glucosides; D006027:Glycosides; D057888:Iridoid Glucosides; D039823:Iridoids; D014344:Trypanocidal Agents; C059515:secoxyloganin; C059516:loganin