CC(C)C[C@@H](CN)NC(=O)c1[nH]cnc1C(=O)N[C@@H](CC(=O)O)C(=O)CNC[C@H](C)NC(=O)c1[nH]cnc1C(=O)N[C@@H](CC(=O)O)C(=O)O.Cl
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?