C[C@]12CC[C@@H]3c4ccc(OP(=O)([O-])O)cc4CC[C@H]3[C@@H]1CCC2=O.[Na+]
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?