Cc1ccc(S(=O)(=O)O)cc1.N/C(=N\O)N/N=C\c1cc([N+](=O)[O-])cc([N+](=O)[O-])c1O
Molecules with a polar surface area of greater than 140 angstroms squared (Å2) tend to be poor at permeating cell membranes. What's the psa of this molecule?