title: New dammarane triterpenes from the aerial parts of Ibicella lutea grown in Argentina.
abstract: Two new dammarane triterpenes have been isolated from the aerial parts of Ibicella lutea, 3-acetyl-24-epi-polacandrin (1) and 1,3-diacetyl-24-epi-polacandrin (2), and were obtained along with the known compounds 20S,24S-epoxy-3beta,12beta,25-trihydroxydammarane (3) and apigenin. The structures of compounds 1 and 2 were deduced by spectroscopic studies and by chemical transformations leading to the preparation of derivatives 4-11. The structure and relative stereochemistry of 1 were verified by single-crystal X-ray analysis. The natural compounds and selected semisynthetic derivatives were evaluated against several tumor cells.
authors.affiliation: INTEQUI-CONICET-Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, 5700 San Luis, Argentina.
authors.forename: Mario J
authors.initials: MJ
authors.lastname: Simirgiotis
authors.forename: Carlos
authors.initials: C
authors.lastname: Jiménez
authors.forename: Jaime
authors.initials: J
authors.lastname: Rodríguez
authors.forename: Oscar S
authors.initials: OS
authors.lastname: Giordano
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Tonn
mesh_terms: D000107:Acetylation; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D001118:Argentina; D045744:Cell Line, Tumor; D018360:Crystallography, X-Ray; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010946:Plants, Medicinal / Q000737:chemistry*; D013237:Stereoisomerism; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000097669:Dammaranes
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D014315:Triterpenes; D000097669:Dammaranes; C482772:1,3-diacetyl-24-epi-polacandrin; C482771:3-acetyl-24-epi-polacandrin