【摘 要】
：
A detailed chemical investigation of the South China Sea nudibranch Hexabranchus sanguineus,as well as its possible sponge-prey Acanthella cavernosa,led to the isolation of fifteen new nitrogenous sesquiterpenoids,namely ximaocavernosins A-O,including sev
【机 构】
：
State Key Laboratory of Drug Research,Shanghai Institute of Materia Medica,Chinese Academy of Scienc
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A detailed chemical investigation of the South China Sea nudibranch Hexabranchus sanguineus,as well as its possible sponge-prey Acanthella cavernosa,led to the isolation of fifteen new nitrogenous sesquiterpenoids,namely ximaocavernosins A-O,including seven cadinanes (1-7),seven spiroaxanes (12-18) and one aromadendrane (19),together with thirteen known related compounds (8-11 and 20-28).Compounds (±)-1-9 (except for 4 and 6) were further separated by chiral-phase HPLC to their corresponding unequal enantiomers,respectively.Their structures and absolute configurations were determined by a combination of extensive spectroscopic data analysis,quantum mechanical nuclear magnetic resonance (QM-NMR) methods,Mosher\'s method,X-ray diffraction analysis and/or time-dependent density functional theory/electronic circular dichroism (TDDFT-ECD) calculation.The commonly existed ni-trogenous sesquiterpenoids in these two animals are suggested to be chemical markers for their prey-predator relationship.
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