Structure of Cucumarioside G₂, a Novel Nonholostane Glycoside from the Sea Cucumber Eupentacta fraudatrix

Abstract

The new triterpene glycoside cucumarioside G2 [1] has been isolated from the sea cucumber Eupentacta fraudatrix. Glycoside 1 is the first triterpene glycoside with the 23,24,25,26,27-pentanorlanostane type of aglycone. Its structure has been established by chemical transformations as well as 13C- and 1H-nmr, eims, and liquid sims studies.

Sea Cucumbers Triterpene Glycosides, the Recent Progress in Structural Elucidation and Chemotaxonomy

“…For example, a series of very interesting from the point of view of their structures relationship mono-and disulfated glycosides was isolated from sea cucumber Pentamera calcigera (the subfamily Thyoninae, the family Phyllophoridae) collected in the Sea of Japan ( Figure 2). Monosulfated glycosides were presented by cucumarioside G 2 (2), earlier isolated from Eupentacta fraudatrix (Avilov et al, 1994) and three new glycosides, calcigerosides B (3), C 1 (4) and C 2 (5) (Avilov et al, 2000a). New glycosides contain branched pentasaccharide carbohydrate chains with 3-O-methylxylose as a terminal residue that is a rare feature for sea cucumber glycosides.…”

Metabolite Profiling of Triterpene Glycosides of the Far Eastern Sea Cucumber Eupentacta fraudatrix and Their Distribution in Various Body Components Using LC-ESI QTOF-MS

“…E. fraudatrix is a well-studied species that is often used as a model organism in biological studies of various processes such as development [16,17], regeneration [18,19,20] and immunity [21,22,23]. The previous investigations of the sea cucumber E. fraudatrix have led to isolation of 37 triterpene glycosides comprising 15 non-sulfated tetraosides (cucumariosides A 1 –A 15 [24,25,26]), two non-sulfated triosides (cucumariosides B 1 and B 2 [27]), two non-sulfated pentaosides (cucumariosides C 1 and C 2 [28]), 4 sulfated tetraosides (cucumariosides G 1 –G 4 [29,30,31,32]), eight sulfated pentaosides (cucumariosides H, H 2 –H 8 [33,34,35]), two disulfated tetraosides (cucumariosides F 1 and F 2 [36]), and four disulfated pentaosides (cucumariosides I 1 –I 4 [37,38]). The majority of the glycosides from E. fraudatrix are characterized by the presence of 3- O -MeXyl residue as terminal unit in carbohydrate chain, which is considered a chemotaxonomic marker of the genus Eupentacta .…”

Absorption and pharmacokinetic study of two sulphated triterpenoid saponins in rat after oral and intravenous administration of saponin extracts of Pearsonothuria graeffei by HPLC-MS

“…Most of the identified sea cucumber glycosides had lanostane aglycones with an 18(20)-lactone and were related to the holostane series, therefore called holostane. Another series of sea-cucumber glycosides with either an 18 (16)-lactone or no lactone aglycones are called nonholostane (Avilov et al, 1994). The monosaccharide constituents of sea cucumber glycosides include D-xylose, D-quinovose, D-glucose, D-3-O-methylglucose and D-3-O-methylxylose (Kalinin, 2000).…”