title: Antifouling activity of a dibrominated cyclopeptide from the marine sponge Geodia barretti.
abstract: Many sessile suspension-feeding marine organisms rely on chemical defense to keep their surfaces free from fouling organisms. The brominated cyclopeptides barettin (cyclo[(6-bromo-8-entryptophan)arginine]) ( 1) and 8,9-dihydrobarettin (cyclo[(6-bromotryptophan)arginine]) ( 2) from the cold-water sponge Geodia barretti have previously displayed settlement inhibition of barnacle larvae in a dose-dependent manner. In this paper, we describe a novel dibrominated cyclopeptide, bromobenzisoxazolone barettin (cyclo[(6-bromo-8-(6-bromobenzioxazol-3(1 H)-one)-8-hydroxy)tryptophan)]arginine) ( 3), which we have isolated from G. barretti and which displays settlement inhibition of barnacle larvae ( Balanus improvisus) with an EC 50 value of 15 nM. The chemical structure was determined using MS and 2D-NMR.
authors.affiliation: Department of Medicinal Chemistry, Uppsala University , Sweden.
authors.forename: Erik
authors.initials: E
authors.lastname: Hedner
authors.forename: Martin
authors.initials: M
authors.lastname: Sjögren
authors.forename: Said
authors.initials: S
authors.lastname: Hodzic
authors.forename: Rolf
authors.initials: R
authors.lastname: Andersson
authors.forename: Ulf
authors.initials: U
authors.lastname: Göransson
authors.forename: Per R
authors.initials: PR
authors.lastname: Jonsson
authors.forename: Lars
authors.initials: L
authors.lastname: Bohlin
mesh_terms: D000818:Animals; D047231:Geodia / Q000737:chemistry*; D006842:Hydrocarbons, Brominated / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects; D008386:Marine Biology; D015394:Molecular Structure; D009792:Oceans and Seas; D010456:Peptides, Cyclic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D013548:Sweden; D001468:Thoracica / Q000187:drug effects / Q000254:growth & development
chemical_list: C484473:8,9-dihydrobarettin; D006842:Hydrocarbons, Brominated; D010456:Peptides, Cyclic; C484472:barettin; C528780:bromobenzisoxazolone barettin