Synonyms: Naphth[2',1':4,5]indeno[1,2-b]oxete,pregnano[17,16-b]oxete deriv.; Naphth[2',1':4,5]indeno[1,2-b]oxete,6b-ethyl-1,2,3,4,4a,4b,5,6,6a,6b,9,9a,9b,10,11,11a-hexadecahydro-4a,6a-dimethyl-,[4aS-(4aa,4bb,6aa,6ba,9ab,9ba)]-; [4aS-(4aa,4bb,6aa,6ba,9ab,9ba)]-6b-Ethyl-1,2,3,4,4a,4b,5,6,6a,6b,9,9a,9b,10,11,11a-hexadecahydro-4a,6a-dimethylnaphth[2',1':4,5]indeno[1,2-b]oxete