title: Discorhabdins revisited: cytotoxic alkaloids from southern australian marine sponges of the genera Higginsia and Spongosorites.
abstract: Chemical analysis of southern Australian marine sponges of the genera Higginsia and Spongosorites has yielded examples of the discorhabdin class of alkaloids. These include the known metabolites (+)-discorhabdin A (1), (+)-discorhabdin D (2), makaluvamine J (6), and damirone A (7), together with four new analogues, (+)-dihydrodiscorhabdin A (3), (+)-debromodiscorhabdin A (4), (+)-dihydrodiscorhabdin L (8), and (+)-discorhabdin X (5), with the latter compound being the first reported example of a thio heterocycle flanked by oxo-thio-acetal and azo-thio-acetal functionalities. Structures for the new compounds were assigned on the basis of detailed spectroscopic interpretation.
authors.affiliation: Centre for Molecular Biodiversity, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, 4072, Australia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: El-Naggar
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Capon
mesh_terms: D000470:Alkaloids / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D018360:Crystallography, X-Ray; D004354:Drug Screening Assays, Antitumor; D008386:Marine Biology; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D011161:Porifera / Q000737:chemistry*; D011809:Quinones / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D013141:Spiro Compounds / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D013237:Stereoisomerism; D013841:Thiazepines / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000470:Alkaloids; D000970:Antineoplastic Agents; D011809:Quinones; D013141:Spiro Compounds; D013841:Thiazepines; C471812:discorhabdin A