CC[C@@H](C)C(NC(=O)OC(C)(C)C)c1cn([C@@H](CCC(=O)OC(C)(C)C)C(=O)N2CCN(C(=O)OC(C)(C)C)CC2)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.