COc1ccccc1CNC(=O)[C@@H](NC(=O)C1CCN(C(=O)[C@@H]2CCCN2C(=O)OC(C)(C)C)CC1)C(C)C
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?