COC(=O)C1=COC(O[C@H]2OC(CO)[C@H](O)C(O)C2O)[C@H]2C1C(=O)C[C@@H]2C
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?