Echingridimer A, an Oxaspiro Dimeric Sesquiterpenoid with a 6/6/5/6/6 Fused Ring System from Echinops grijsii and

Tingting Liu1, Haibo Wu2, Hongyun Jiang1

  • 1Key Laboratory of Control of Biological Hazard Factors (Plant Origin) for Agriproduct Quality and Safety, Ministry of Agriculture and Rural Affairs of the People's Republic of China , Institute of Plant Protection, Chinese Academy of Agricultural Sciences , Beijing 100193 , China.

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