title: Structure of cucumariosides H5, H6, H7 and H8, triterpene glycosides from the sea cucumber Eupentacta fraudatrix and unprecedented aglycone with 16,22-epoxy-group.
abstract: Four new triterpene glycosides cucumariosides H5 (1), H6 (2), H7 (3) and H8 (4) along with the known cucumarioside H (5) have been isolated from the Far Eastern sea cucumber Eupentacta fraudatrix. The structures of glycosides 1-4 were elucidated on the basis of spectral data (2D NMR and MS). Glycosides 1-4 belong to the group o f cucumariosides H having branched rare pentasaccharidecarbohydrate moieties with one sulfate group and 3-O-methyl-D-xylose as a terminal monosaccharide unit. Glycosides 1-3 and 5 differ from each other in structures of side chains of the aglycones, while cucumarioside H8 (4) has a novel aglycone with unprecedented 16(22)-epoxy-group, never found in the sea cucumbers glycosides. Glycosides 1-3, and 5 were cytotoxic against mouse lymphocytes and hemolytic against mouse erythrocytes. Glycoside 2 was less active in comparison with others.
authors.affiliation: Pacific Institute of Bioorganic Chemistry of the Far East Division of the Russian Academy of Sciences, Pr. 100-letya Vladivostoka 159, 690022, Vladivostok, Russian Federation.
authors.forename: Alexandra S
authors.initials: AS
authors.lastname: Silchenko
authors.forename: Anatoly I
authors.initials: AI
authors.lastname: Kalinovsky
authors.forename: Sergey A
authors.initials: SA
authors.lastname: Avilov
authors.forename: Pelageya V
authors.initials: PV
authors.lastname: Andryjaschenko
authors.forename: Pavel S
authors.initials: PS
authors.lastname: Dmitrenok
authors.forename: Ekaterina A
authors.initials: EA
authors.lastname: Yurchenko
authors.forename: Vladimir I
authors.initials: VI
authors.lastname: Kalinin
mesh_terms: D000818:Animals; D006027:Glycosides / Q000737:chemistry*; D008214:Lymphocytes / Q000187:drug effects; D051379:Mice; D015394:Molecular Structure; D012616:Sea Cucumbers / Q000737:chemistry*; D013154:Spleen / Q000166:cytology; D014315:Triterpenes / Q000737:chemistry*
chemical_list: D006027:Glycosides; D014315:Triterpenes