COc1ccc(CC(NC(C)=O)C(=O)NC2CCN(C(=O)c3ccc([N+](=O)[O-])cc3)CC2)cc1OC
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?