CC(C(=O)OCC(=O)c1cccc([N+](=O)[O-])c1)N1C(=O)C2C3C=CC(C3)C2C1=O
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?