Synonyms: Spiro[17H-cyclopenta[a]phenanthrene-17,4'-[1,3,2]dioxathiolane],spiro[1,3,2-dioxathiolane-4,17'-estrane] deriv.;Spiro[17H-cyclopenta[a]phenanthrene-17,4'-[1,3,2]dioxathiolane],hexadecahydro-13-methyl-, [8R-(8a,9b,10a,13a,14b)]-; [8R-(8a,9b,10a,13a,14b)]-Hexadecahydro-13-methylspiro[17H-cyclopenta[a]phenanthrene-17,4'-[1,3,2]dioxathiolane]