Laevinoids A and B: Two Diterpenoids with an Unprecedented Backbone from <i>Croton laevigatus</i>

Chemical fractionation of the ethanolic extract of a Chinese herbal plant, <i>Croton laevigatus</i>, yielded laevinoids A (<b>1</b>) and B (<b>2</b>) with a new rearranged <i>ent</i>-clerodane scaffold named as laevinane. The structures of <b>1</b> and <b>2</b> were assigned on the basis of detailed spectroscopic analyses with their absolute configurations being established via single-crystal X-ray diffraction studies