title: Absolute structures and bioactivities of euryspongins and eurydiene obtained from the marine sponge Euryspongia sp. collected at Iriomote Island.
abstract: Three unique sesquiterpenes, named euryspongins A-C (1-3), have been isolated from the marine sponge Euryspongia sp. The absolute configuration of 1 was assigned as (4R,6R,9S) by comparing its experimental Electronic Circular Dichroism (ECD) spectrum with the calculated ECD spectra of both enantiomers, and the absolute configurations of 2, 3 and artifact 4 were suggested on the basis of that of 1 by assuming common biogenesis of 1-3. These absolute configurations were opposite to those depicted in the previous communication. Further separation of the remaining fractions lead to the isolation of a new C11-polyketide, named as eurydiene (5), together with a known C11-polyketide, nakitriol (6). The structure of 5 was assigned on the basis of its spectroscopic data as a bicyclic alcohol with a diene side chain. Dehydroeuryspongin A (4) inhibited protein tyrosine phosphatase 1B (PTP1B), an important target enzyme for the treatment of type II diabetes and obesity, with an IC50 value of 3.58μM. Moreover, compound 4 did not inhibit the proliferation of human hepatoma Huh-7 cells at 100μM. One of the locations in which PTP1B has been detected is hepatocytes. Compounds 1-3, 5, and 6 were not active against PTP1B. The growth of human colon (HCT-15) and T-cell lymphoma (Jurkat) cells was not disturbed by compounds 1-6.
authors.affiliation: Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yamazaki
authors.affiliation: Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan.
authors.forename: Ohgi
authors.initials: O
authors.lastname: Takahashi
authors.affiliation: Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan.
authors.forename: Syu-Ichi
authors.initials: S
authors.lastname: Kanno
authors.affiliation: Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nakazawa
authors.affiliation: Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan.
authors.forename: Shiori
authors.initials: S
authors.lastname: Takahashi
authors.affiliation: Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan.
authors.forename: Kazuyo
authors.initials: K
authors.lastname: Ukai
authors.affiliation: Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan; Faculty of Fisheries and Marine Science, Sam Ratulangi University, Kampus Bahu, Manado 95115, Indonesia.
authors.forename: Deiske A
authors.initials: DA
authors.lastname: Sumilat
authors.affiliation: Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Ishikawa
authors.affiliation: Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan. Electronic address: mnami@tohoku-pharm.ac.jp.
authors.forename: Michio
authors.initials: M
authors.lastname: Namikoshi
mesh_terms: D000818:Animals; D001688:Biological Products / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy / Q000201:enzymology; D006801:Humans; D008958:Models, Molecular; D009369:Neoplasms / Q000188:drug therapy; D011161:Porifera / Q000737:chemistry*; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D012717:Sesquiterpenes / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D001688:Biological Products; D012717:Sesquiterpenes; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1
keywords: Eurydiene; Euryspongia sp.; Euryspongin; Marine sponge; PTP1B