(1aR,1bR,2'S,3S,5aR,5bS,7aS,8aS,9aS,9bS,9cR,9dR)-Hexadecahydro-5a,7a-dimethylspiro[8H-cyclopropa[l]cyclopropa[4,5]cyclopenta[1,2-a]phenanthrene-8,2'-oxirane]-1b,3(2H)-diol