1. Diterpenoids from Isodon species and their biological activities
2. In the Pharmacopoecia of People’s Repulic of China; People’s Health Press:Beijing, 1977; p186.
3. Enantioselective Synthesis of β-Trifluoromethyl-β-lactones via NHC-Catalyzed Ketene−Ketone Cycloaddition Reactions
4. Colorless laminate crystals of rubesanolide A (from MeOH) belong to the monoclinic space groupP21. The crystal data: C20H30O4,M= 334,a= 6.301(3) Å,b= 11.371(8) Å,c= 13.236(8) Å, β = 95.602 (16)°,V= 943.8(10) Å3,Z= 2,d= 1.177g/cm3. A crystal of dimensions 0.02 × 0.27 × 0.46 mm3was used for measurements on a Rigaku MicroMax 002+ diffractometer with a graphite monochromator (ω-κ scans, 2θmax = 145.72°), Cu Kα radiation. The total number of independent reflections measured was 3259, of which 2900 were observed (|F|2≥ 2σ|F|2). The crystal structure was solved and refined by the direct method SHELXS-97(Sheldrick, G. M.University of Gottingen:Gottingen, Germany, 1997, ), expanded using difference Fourier techniques and full-matrix least-squares calculations. Final indices:R1= 0.0403,wR2= 0.1039 (w= 1/σ|F|2),s= 1.016. Crystallographic data for the structure of1have been deposited in the Cambridge Crystallographic Data Centre (Deposition No. CCDC798778). Copies of these data can be obtained, free of charge, on application to the CCDC via the Internet atwww.ccdc.com.ac.uk/conts/retrieving.html(or 12 Union Road, Cambridge CB2 1EZ, UK, fax: +44 1223 336033, e-mail:deposit@ccdc.cam.ac.uk).