| Abstract
| - Four new triterpene glycosides, cucumariosides A2-5 (1), A3-2 (2), A3-3 (3), and isokoreoside A (4), alongwith 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 identifiedthrough 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 pentasaccharidecarbohydrate 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 sidechains, which is a very rare feature among the sea cucumber glycosides.
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