Variegatusides: new non-sulphated triterpene glycosides from the sea cucumber Stichopus variegates semper.
Four new triterpene glycosides, variegatusides C-F (1-4), together with three structurally known triterpene glycosides, variegatusides A and B (5, 6), and holothurin B (7), were isolated from the sea cucumber Stichopus variegates Semper (Holothuriidae), collected from the South China Sea. Their structures were elucidated on the basis of extensive spectral analysis (nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESIMS)) and chemical evidence. Variegatusides C-F exhibit the same structural feature consisting of the presence of a 23-hydroxyl group at the holostane-type triterpene aglycone side chain. Variegatuside C (1) has a double bond (24, 25) in this same chain, while variegatuside D (2) exhibits a 8(9)-ene bond in the holostane-type triterpene aglycone, which has not been extracted from other sea cucumber species. Compound 4 is a native compound from the sea cucumber S. variegates Semper, which has been reported to be desacetylstichloroside B₁. Except for holothurin B, these glycosides have no sulfate group in their sugar chain and show potent antifungal activities in vitro biotests.
Research Center for Marine Drugs, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai 200433, China. wangxiaohua737@sina.com.
Xiao-Hua
XH
Wang
College of Life Science, Jiangxi Normal University, 99 Ziyang Road, Nanchang 330022, China. zouzhr@163.com.
Zheng-Rong
ZR
Zou
Research Center for Marine Drugs, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai 200433, China. yiyanghua@hotmail.com.
Yang-Hua
YH
Yi
Research Center for Marine Drugs, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai 200433, China. hanhua@tongji.edu.cn.
Hua
H
Han
Research Center for Marine Drugs, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai 200433, China. lilingty@hotmail.com.
Ling
L
Li
Research Center for Marine Drugs, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai 200433, China. virgen2008@hotmail.com.
Min-Xiang
MX
Pan
D000818:Animals; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002681:China; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D021241:Spectrometry, Mass, Electrospray Ionization; D047528:Stichopus / Q000378:metabolism*; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
D000935:Antifungal Agents; D006027:Glycosides; D014315:Triterpenes