The structure of penduliflaworosin, a new furanoid diterpene from Croton penduliflorus

A clerodane-type diterpene has been isolated from the roots of Croton penduliflorus Hutch. (Euphorbiaceae). Spectroscopic evidence and chemical degradation have shown its structure to be ent-(12R)-methyl-15,16-epoxy-9,10-friedolabda-5(10),13(16),14-trien-19-oate 20,12-lactone (4).