title: New triterpenoid sulfates from the red alga Tricleocarpa fragilis.
abstract: Ten new sulfated terpenoids, including six cycloartenol sulfates (1-6), two 29-nor-cycloartenol sulfates (7,8), and two 29-nor-lanosterol sulfates (9,10), were isolated from brine shrimp-toxic fractions of the methanolic extract of the red alga Tricleocarpa fragilis collected in Hawaiian waters. Structures 1-10 were elucidated by spectral methods, and the absolute stereochemistry for compound 1 at C23 was determined by Mosher analysis. Compounds 7 and 10 showed brine shrimp toxicity at 50 microg/mL, while 1 and 3 showed substantial activity at 17 microg/mL. Compounds 2, 4, 5, and 9 were inactive. In cytotoxicity assays, compounds 1-10 were inactive at concentrations tested.
authors.affiliation: Department of Chemistry, University of Hawaii at Manoa, 2545 The Mall, Honolulu, Hawaii 96822, USA.
authors.forename: F D
authors.initials: FD
authors.lastname: Horgen
authors.forename: B
authors.initials: B
authors.lastname: Sakamoto
authors.forename: P J
authors.initials: PJ
authors.lastname: Scheuer
mesh_terms: D000818:Animals; D001156:Artemia; D002851:Chromatography, High Pressure Liquid; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D007941:Leukemia P388 / Q000188:drug therapy; D009682:Magnetic Resonance Spectroscopy; D000461:Rhodophyta / Q000737:chemistry*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013055:Spectrophotometry, Infrared; D013431:Sulfates; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000633:toxicity
chemical_list: D013431:Sulfates; D014315:Triterpenes