title: Triterpene glycosides from the Far Eastern sea cucumber Cucumaria conicospermium.
abstract: Four new triterpene glycosides, cucumariosides A(2)-5 (1), A(3)-2 (2), A(3)-3 (3), and isokoreoside A (4), along with the previously isolated koreoside A (5), have been found in the sea cucumber Cucumariaconicospermium. Glycoside 1 was isolated as a native substance, while glycosides 2-5 were identified through their desulfated derivatives. Their structures have been deduced by extensive spectral analysis (NMR and MS) and chemical evidence. All the glycosides contain the same branched pentasaccharide carbohydrate chain but differ in the number and positions of the sulfate groups. Glycoside 1 has one, glycosides 2 and 3 have two, and glycosides 4 and 5 have three sulfate groups. Glycosides 2-5 are non-holostane derivatives; their aglycons lack the 18(20)-lactone and are characterized by shortened side chains, which is a very rare feature among the sea cucumber glycosides.
authors.affiliation: Pacific Institute of Bioorganic Chemistry, the Far East Division of the Russian Academy of Sciences, 690022, Vladivostok, Russian Federation. avilov@piboc.dvo.ru
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Avilov
authors.forename: Alexandr S
authors.initials: AS
authors.lastname: Antonov
authors.forename: Alexandra S
authors.initials: AS
authors.lastname: Silchenko
authors.forename: Vladimir I
authors.initials: VI
authors.lastname: Kalinin
authors.forename: Anatoly I
authors.initials: AI
authors.lastname: Kalinovsky
authors.forename: Pavel S
authors.initials: PS
authors.lastname: Dmitrenok
authors.forename: Valentin A
authors.initials: VA
authors.lastname: Stonik
authors.forename: Ricardo
authors.initials: R
authors.lastname: Riguera
authors.forename: Carlos
authors.initials: C
authors.lastname: Jimenez
mesh_terms: D000818:Animals; D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification*; D007564:Japan; D013058:Mass Spectrometry; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D012616:Sea Cucumbers / Q000737:chemistry*; D013237:Stereoisomerism; D014315:Triterpenes / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D006027:Glycosides; D014315:Triterpenes