5H-Benzo[3,4]furo[3',4':5,6]cyclohepta[1,2-f][1,3]benzodioxol-5-one, 4b,7,7a,8-tetrahydro-8-hydroxy-1,2,3-trimethoxy-, (4b.alpha.,7a.beta.,8.beta.)- NSC172959 STEGANOL