CC1=C(C(=O)OC(C)C)C(c2cccc([N+](=O)[O-])c2)C(C(=O)OC(CO[N+](=O)[O-])CO[N+](=O)[O-])=C(C)N1
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.