Synonyms: Piceno[3,4-b]furan,2'H-24-norursano[3,4-b]furan deriv.; Piceno[3,4-b]furan,3a,3b,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a,13b,14,15,15a-docosahydro-3a,5a,5b,7a,10,11,13b-heptamethyl-,[3bR-(3ba,5ab,5ba,7ab,10a,11b,11ab,11bb,13aa,13bb)]-; [3bR-(3ba,5ab,5ba,7ab,10a,11b,11ab,11bb,13aa,13bb)]-3a,3b,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a,13b,14,15,15a-Docosahydro-3a,5a,5b,7a,10,11,13b-heptamethylpiceno[3,4-b]furan