CCN(CC)c1ncnc2c1ncn2[C@@H]1O[C@H](COP(=O)([O-])OP(=O)([O-])C(Br)(Br)P(=O)([O-])O)[C@@H](O)[C@@H]1O.[Na+].[Na+].[Na+]
PSA is a commonly used medicinal chemistry metric for the optimization of a drug's ability to permeate cells. Please predict psa of this molecule.