phyllostachysin A

[4aR,11aα,12R,13R,(-)]-2,3,4a,9,10,11,11a,11b-Octahydro-6α,11α,12,13-tetrahydroxy-4,4-dimethyl-8-methylene-6β,11bβ:6aβ,9β-dimethano-1H-cyclohepta[a]naphthalene-5,7(6H,8H)-dione