CC[C@@H](C)[C@@H](C(=O)N1CCN(C(=O)OC(C)(C)C)CC1)n1cc(CCCN=C(NC(=O)OC(C)(C)C)NC(=O)OC(C)(C)C)nn1
PSA is a commonly used medicinal chemistry metric for the optimization of a drug's ability to permeate cells. Please predict psa of this molecule.