C[C@H](CCC(=O)NCC(=O)O)[C@H]1CC[C@H]2[C@@H]3[C@@H](O)C[C@H]4C[C@@H](O)CC[C@@]4(C)[C@@H]3C[C@@H](O)[C@@]21C
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?