O=C(Nc1ccc[n+](-c2nc3ccccc3nc2[N-]S(=O)(=O)c2ccccc2)c1)c1ccc(Cl)cc1
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?