(1<i>S*</i>,2<i>S*</i>,5<i>R*</i>,8<i>S*</i>,11<i>S*</i>,14<i>R*</i>,17<i>S*</i>,20<i>R*</i>)-14-Methyl-6-methylene-10,16,18-trioxahexacyclo[12.5.1.1<sup>5,8</sup>.0<sup>1,11</sup>.0<sup>2,8</sup>.0<sup>17,20</sup>]henicosane-7,9-dione: natural diterpenoid macrocalyxoformin B
Acta crystallographica. Section E