Bismuthate(2-), (1,7-dihydro-6H-purine-6-thionato-S)bis(1,9-dihydro-6H-purine-6-thionato-N(7),S(6))oxo-, disodium Bismuthate(2-), (1,7-dihydro-6H-purine-6-thionato-S)bis(1,9-dihydro-6H-purine-6-thionato-N7,S6)oxo-, disodium NSC70088