Novel Nardosinane Type Sesquiterpenoids from Nardostachys chinensis Batal.

Abstract Five new sesquiterpenoids Nardosinanone A–E (1–5), were isolated from the extract of Nardostachys chinensis, and their structures were determined by extensive spectroscopic analysis. Compound 1 featured a nardosinane sesquiterpenoid with an unusual tricyclic skeleton. Compounds 2–4 were new nardosinane sesquiterpenoids bearing a rare 10,11-epoxy group. The absolute configurations were determined by single-crystal X-ray diffraction analysis, ECD calculation method, the CD analysis of the in situ formed [Rh2(OCOCF3)4] complex, and the CD data analysis based on the octane rule of cyclohexanone.