COC(=O)C[C@H](COCc1ccccc1)NC(=O)C[C@H](COCc1ccccc1)NC(=O)C[C@H](COCc1ccccc1)NC(=O)OC(C)(C)C
Molecules with a polar surface area of greater than 60 angstroms squared (Å2) is hard to pass brain blood barrier. What's the psa of this molecule?