CC(C)C[C@H]1CNC(=S)N1CC1CCCN1C[C@H](CC(C)C)N1C[C@H](CC(C)C)N(CCc2ccccc2)C1=S
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.