New diterpene glycosides of the fungus Acremonium striatisporum isolated from a sea cucumber

Abstract

Three new diterpene glycosides, virescenosides V (1), W (2), and X (3) have been isolated from a marine strain of Acremonium striatisporum KMM 4401 associated with the holothurian Eupentacta fraudatrix. Their structures have been elucidated on the basis of high resolution mass spectrometry, 1D and 2D NMR (¹H, ¹³C, DEPT, COSY 45, COSY RCT, HSQC, HMBC, and NOESY spectra) as 19-O-β-D-altropyranosyl-7-oxo-isopimara-8(14),15-diene-2α,3β-diol (1), 19-O-β-D-altropyranosyl-isopimara-7,15-diene-2α,3β,6α-triol (2), and 19-O-β-D-altropyranosyl-isopimara-8,15-diene-2α,3β,7α-triol (3).

Keywords:

• Acremonium striatisporum
• Diterpene glycosides
• Marine fungi

Acknowledgment

This work was supported financially by grants of the Russian Foundation for Basic Research (projects No. 03-04-49528, 05-04-48291), a grant of the RF President No. 1237.2003.4, grant No. 2-2.16 of the Federal Agency for Science and Innovation of the Ministry of Education and Science of the RF, and grant No. 04-1-05-005 of the RAS Presidium “Molecular and Cellular Biology”.