O=C(Cc1ccc([N+](=O)[O-])c([N+](=O)[O-])c1CC(=O)C(=O)Nc1cc(Cl)ccc1Cl)C(=O)Nc1cc(Cl)ccc1Cl
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.