C[N@+]1([O-])[C@@H]2C[C@H](OC(=O)[C@@H](CO)c3ccccc3)C[C@@H]1[C@H]1O[C@H]12
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?