Structures and biological activities of cladolosides C3, E1, E2, F1, F2, G, H1 and H2, eight triterpene glycosides from the sea cucumber Cladolabes schmeltzii with one known and four new carbohydrate chains. (23rd September 2015)

• Record Type: Journal Article
• Authors: Silchenko, Alexandra S.; Kalinovsky, Anatoly I.; Avilov, Sergey A.; Andryjaschenko, Pelageya V.; Dmitrenok, Pavel S.; Yurchenko, Ekaterina A.; Dolmatov, Igor Yu.; Kalinin, Vladimir I.
• Is Part Of: Carbohydrate research. Volume 414(2015)
• Page Start: 22
• Page End: 31
• Publication Date: 2015-09-23
• Subjects: Cladolabes schmeltzii -- Triterpene glycosides -- NMR -- Cytotoxic activity; Carbohydrates -- Periodicals; Chemistry, Organic -- Periodicals; Biochemistry -- Periodicals; Carbohydrates -- Periodicals; Chimie organique -- Périodiques; Glucides -- Périodiques; Biochemistry; Carbohydrates; Chemistry, Organic; Periodicals; Electronic journals; 507.78
• DOI: 10.1016/j.carres.2015.06.005
• Languages: English
• ISSNs: 0008-6215

Abstract

Abstract: Eight new nonsulfated triterpene glycosides, cladolosides C3 (1 ), E1 (2 ), E2 (3 ), F1 (4 ), F2 (5 ), G (6 ), H1 (7 ) and H2 (8 ) have been isolated from the tropical Indo-West Pacific sea cucumber Cladolabes schmeltzii (Cladolabinae, Sclerodactylidae, Dendrochirotida) collected in the Vietnamese shallow waters. The structures of the glycosides were elucidated by 2D NMR spectroscopy and mass-spectrometry. Glycosides2, 3, 4, and5 have pentasaccharide branched carbohydrate moieties and differ from each other by monosaccharide compositions and aglycone structures. At that, glycosides2 and3 contain three xylose, one 3-O-methyl-glucose and one quinovose residues, while glycosides4 and5 have two quinovose, two xylose and one 3-O-methyl-glucose residues. Compounds1 and6 –8 are hexaosides differing from each other by aglycone structures and by the fifth monosaccharide residue, which proved to be glucose in cladoloside C3 (1 ), xylose in cladoloside G (6 ) and quinovose in cladolosides H1 (7 ) and H2 (8 ). The presence of quinovose residue in the fifth position, as in4, 5, 7 and8 has never been earlier found in carbohydrate chains of triterpene glycosides from sea cucumbers. The carbohydrate chains with xylose in the fifth position of pentaosides and hexaosides are also very unusual for holothurious glycosides. All the substances demonstrate strong or moderate cytotoxic and hemolytic effects with hexaosides being more active than the corresponding pentaosides. Peculiarities of the biosynthesis and biochemical evolution of glycosides of this type are discussed. Graphical abstract: Highlights: Eight new nonsulfated triterpene glycosides were isolated from Cladolabes schmeltzii . Four new pentasaccharide and three hexasaccharide carbohydrate chains were found. The presence of quinovose as fifth sugar is unique.