Crystal Structure of the ER-alpha Ligand-binding Domain in Complex with a Sulfoxide-bridged Oxabicyclic Heptene Sulfonate (SOBHS)-3 analog phenyl (1S,2S,4S,7S)-5,6-bis(4-hydroxy-3-methylphenyl)-7-thiabicyclo[2.2.1]hept-5-ene-2-sulfonate 7-oxide