title: Phorbasterones A-D, cytotoxic nor-ring A steroids from the sponge Phorbas amaranthus.
abstract: The sponge Phorbas amaranthus from Florida contains the new ring A-contracted steroids, phorbasterones A-D, and the known anthosterones A and B. The structures of phorbasterones A-D were determined by interpretation of their spectroscopic data. Phorbasterones show moderate cytotoxicity against HCT-116 tumor cells.
authors.affiliation: Department of Chemistry, University of California, Davis, California 95616, USA.
authors.forename: Makoto N
authors.initials: MN
authors.lastname: Masuno
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Pawlik
authors.forename: Tadeusz F
authors.initials: TF
authors.lastname: Molinski
mesh_terms: D000818:Animals; D004354:Drug Screening Assays, Antitumor; D005431:Florida; D045325:HCT116 Cells; D006801:Humans; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D009792:Oceans and Seas; D011161:Porifera / Q000737:chemistry*; D013256:Steroids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D013256:Steroids