title: Dibromotyrosine and histamine derivatives from the tropical marine sponge Aplysina sp.
abstract: Two new compounds, 3-amino-7,8-dihydroimidazo-[1,5-c]-pyrimidin-5(6H)-one (1) and ethyl 3-(2-amino-1H-imidazol-4-yl)propylcarbamate (2), along with the previously known 7,8-dihydroimidazo-[1,5-c]-pyrimidin-5(6H)-one (3), aeroplysinin-1 (4), dibromoverongiaquinol (5), bisoxazolidinone derivative (6), aerophobins-1 (7) and -2 (8), purealidins J (9) and L, have been isolated from Aplysina sp. from the South China Sea. The structures were elucidated on the basis of 1H, 13C NMR, MS and IR analyses. The histamine-derived alkaloids 1-3 may be unknown bioconversion products of purealidin J (9), aerophobin-2 (8) and aerophobin-1 (7), respectively, when 7-9 are cleaved at C-8-C-9 in reactions of activated chemical defense in Aplysina sponge.
authors.affiliation: Laboratory of Marine Natural Products Chemistry, Pacific Institute of Bioorganic Chemistry of the Far-Eastern Branch of the Russian Academy of Science, Vladivostok 690022, Prospect 100-let Vladivostoku, 159, Russia. santalova@www.piboc.dvo.ru
authors.forename: Elena A
authors.initials: EA
authors.lastname: Santalova
authors.forename: Vladimir A
authors.initials: VA
authors.lastname: Denisenko
authors.forename: Valentin A
authors.initials: VA
authors.lastname: Stonik
mesh_terms: D000818:Animals; D002219:Carbamates / Q000737:chemistry* / Q000302:isolation & purification; D002855:Chromatography, Thin Layer; D006632:Histamine / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000302:isolation & purification; D007093:Imidazoles / Q000737:chemistry* / Q000302:isolation & purification; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D011161:Porifera / Q000737:chemistry*; D011744:Pyrimidinones / Q000737:chemistry* / Q000302:isolation & purification; D021241:Spectrometry, Mass, Electrospray Ionization; D013055:Spectrophotometry, Infrared; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: C549309:3-amino-7,8-dihydroimidazo-(1,5-c)-pyrimidin-5(6H)-one; D002219:Carbamates; D007093:Imidazoles; D007202:Indicators and Reagents; D011744:Pyrimidinones; C549308:ethyl 3-(2-amino-1H-imidazol-4-yl)propylcarbamate; D014443:Tyrosine; D006632:Histamine