C[C@@]12CC[C@@H](O)C[C@H]1CC[C@@H]1[C@@H]2CC[C@@]2(C)[C@H](O)CC[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?