Synonyms: 16,24-Cyclo-21-nor-13,17-secochol-20(22)-ene-4-carboxylicacid, 13,16-epoxy-19-hydroxy-4,8-dimethyl-17,23-dioxo-, d-lactone, (4b,5a,16S)-;Spiro[3-cyclohexene-1,2'-[9H-6,9a]propano[2H]furo[3',2':5,6]naphtho[1,2-c]pyran]-2,5,7'(3'H)-trione,3'a,3'b,4',5',5'a,6',9'b,10',11',11'a-decahydro-3'b,6',11'a-trimethyl-,(1S,3'aS,3'bR,5'aR,6'S,9'aS,9'bS,11'aS)- (9CI); (-)-Strongylophorin 6;Spiro[3-cyclohexene-1,2'-[9H-6,9a]propano[2H]furo[3',2':5,6]naphtho[1,2-c]pyran]-2,5,7'(3'H)-trione,3'a,3'b,4',5',5'a,6',9'b,10',11',11'a-decahydro-3'b,6',11'a-trimethyl-,[2'S-(2'a,3'ab,3'ba,5'ab,6'b,9'ab,9'bb,11'aa)]-; Strongylophorin 6