CNC1C(O)[C@@H]2OC(O[C@@H]3C(O)C(O)C(N)C[C@H]3N)C(N)C[C@H]2O[C@H]1O[C@@H]1OC(CO)C(N)C(O)C1O
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?