title: JBIR-56 and JBIR-57, 2(1H)-pyrazinones from a marine sponge-derived Streptomyces sp. SpD081030SC-03.
abstract: Strain SpD081030SC-03, representing a novel species of Streptomyces, was isolated from a marine sponge. Two 3,5,6-trisubstituted 2(1H)-pyrazinones, JBIR-56 (1) and JBIR-57 (2), were isolated from a culture of SpD081030SC-03. The planar structures of 1 and 2 were assigned on the basis of extensive NMR and MS analyses. In addition, analyses of the methylated derivative of 1 confirmed a 3,5,6-trisubstituted 2(1H)-pyrazinone moiety. The absolute configurations of the amino acid residues were determined by application of Marfey's method. Because 1 did not appear to comprise the normal connection of amino acid units, we confirmed its structure by the total synthesis of 1. Biosynthetically, 1 consists of a unique skeleton connected to the peptide chain at C-5 of the pyrazinone ring.
authors: Biomedicinal Information Research Center (BIRC), Japan Biological Informatics Consortium (JBIC), 2-4-7 Aomi, Koto-ku, Tokyo 135-0064, Japan.
authors: Keiichiro
authors: K
authors: Motohashi
authors: Kennichi
authors: K
authors: Inaba
authors: Shinichiro
authors: S
authors: Fuse
authors: Takayuki
authors: T
authors: Doi
authors: Miho
authors: M
authors: Izumikawa
authors: Shams Tabrez
authors: ST
authors: Khan
authors: Motoki
authors: M
authors: Takagi
authors: Takashi
authors: T
authors: Takahashi
authors: Kazuo
authors: K
authors: Shin-ya
mesh_terms: D000818:Animals; D008386:Marine Biology; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D009842:Oligopeptides / Q000737:chemistry / Q000302:isolation & purification*; D011161:Porifera / Q000382:microbiology*; D011719:Pyrazines / Q000737:chemistry / Q000302:isolation & purification*; D013302:Streptomyces / Q000737:chemistry*
chemical_list: C561553:JBIR-56; C561554:JBIR-57; D009842:Oligopeptides; D011719:Pyrazines