O=C1C(c2ccccc2)=C(c2ccccc2)[C@H](c2ccccc2)[C@]1(Cc1nnn(-c2ccc([N+](=O)[O-])cc2)c1N1CCOCC1)c1ccccc1
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?