This invention relates to compounds that are mammalian metabolites of (-)-cis-6-phenyl-5-[4-(2-pyrrolidin-1-yl-ethoxy)-phenyl]-5,6,7,8-tetrahyd- ro-naphthalene-2-ol. The compounds of the invention can be used as standards for analytical assays or as intermediates for the further chemical synthesis or biosynthesis of chemical entities. The invention also relates to pharmaceutical compositions for the treatment of disease and methods of treating disease.