O=C1c2c(O)cc(O)cc2O[C@@]12c1c(cc(O)c3c1O[C@H](c1ccc(O)cc1)[C@@H](O)C3)O[C@@H]2c1ccc(O)cc1
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?