title: Four new bromotryptamine derivatives from the marine bryozoan Flustra foliacea.
abstract: Ten brominated alkaloids, 6-bromo-2-(1,1-dimethyl-2-propenyl)-1H-indole-3-carbaldehyde (1), N-(2-[6-bromo-2-(1,1-dimethyl-2-propenyl)-1H-indol-3-yl]ethyl)-N-methylmethanesulfonamide (2), deformylflustrabromine (3), flustrabromine (4), (3aR,8aS)-6-bromo-3a-[(2E)-3,7-dimethyl-2,6-octadienyl]-1,2,3,3a,8,8a-hexahydropyrrolo[2,3-b]-indol-7-ol (5), flustramine C (6), dihydroflustramine C (7), flustramine A (8), flustramine D (9), and flustraminol A (10), and the diterpene 4,6-bis(4-methylpent-3-en-1-yl)-6-methylcyclohexa-1,3-diene-carbaldehyde (11) were isolated from the dichloromethane extract of the North Sea bryozoan Flustra foliacea. Of the 10, four (1, 2, 3, and 5) represent new natural products. The structures of all isolates were elucidated by interpretation of their spectroscopic data (NMR, MS, UV, and IR). For compound 4 complete (13)C NMR data are reported for the first time. Compounds 3 and 6-8 were tested on voltage-activated potassium and sodium channels. Flustramine A (8) shows an unspecific blocking activity on Kv1.4 potassium-mediated currents.
authors.affiliation: Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, D-53115 Bonn, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Peters
authors.forename: Gabriele M
authors.initials: GM
authors.lastname: König
authors.forename: Heinrich
authors.initials: H
authors.lastname: Terlau
authors.forename: Anthony D
authors.initials: AD
authors.lastname: Wright
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D000818:Animals; D002013:Bryozoa / Q000737:chemistry*; D026121:Indole Alkaloids; D051665:Kv1.4 Potassium Channel; D013058:Mass Spectrometry; D015394:Molecular Structure; D009659:North Sea; D019906:Nuclear Magnetic Resonance, Biomolecular; D015221:Potassium Channels / Q000187:drug effects; D024642:Potassium Channels, Voltage-Gated; D051381:Rats; D015222:Sodium Channels / Q000187:drug effects; D014981:Xenopus
chemical_list: D000470:Alkaloids; D026121:Indole Alkaloids; C496979:Kcna4 protein, rat; D051665:Kv1.4 Potassium Channel; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D015222:Sodium Channels; C041253:flustramine A