Trans-dimer D, a novel dimeric sesquiterpene with a bis-bisabolene skeleton from a Hainan sponge Axinyssa variabilis

Abstract

A novel bisabolene sesquiterpene dimer named trans-dimer D (1) and its diastereoisomer trans-dimer C (2) reported in our previous work have been isolated as an inseparable mixture in a ratio of 1.5:1 from the South China Sea sponge Axinyssa variabilis. The structure of 1 was determined on the basis of extensive spectroscopic analysis and by comparison of its NMR spectral data with those of structurally related compounds. Compound 1 represents the fourth example of a sesquiterpene dimer with a bis-bisabolene skeleton.

Keywords:

• sponge
• Axinyssa variabilis
• trans-dimer D
• bis-bisabolene

Acknowledegments

This research work was financially supported by the National Science & Technology Major Projects (Nos. 2009ZX09301-001 and 2009ZX09103-060), the Natural Marine ‘863’ Project (2011AA090071-2), the Natural Science Foundation of China (Nos. 30730108 and 21021063), the EU 7th Framework Program-IRSES Project (2010-2014), the STCSM International Cooperation Project between SIMM/China and ICB/Italy (No. 10540702900), the NSFC-TRF International Cooperation Project (No. 20911140471), and the Foundation of Chinese Academy of Sciences (Grant KSCX2-YW-R-18).