C[C@H]1C[C@@H](C)CN(S(=O)(=O)c2cc(Cl)c(Oc3ccc([N+](=O)[O-])cc3Cl)c(Cl)c2)C1
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?