title: (1S*,2S*,5R*,8S*,11S*,14R*,17S*,20R*)-14-Methyl-6-methyl-ene-10,16,18-trioxa-hexa-cyclo-[12.5.1.1.0.0.0]henicosane-7,9-dione: natural diter-penoid macrocalyxoformin B.
abstract: The title compound, C(20)H(24)O(5), isolated from Rabdosia var. lophanthoides Hara, is built up from six fused rings. Cyclo-hexane ring A adopts a chair conformation, ring B exists in a screw-boat conformation and ring C adopts a boat conformation; the three five-membered rings D, E and F adopt envelope conformations.
authors.affiliation: The College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Shi