CC(=O)O[C@]1(C(C)=O)CC[C@@H]2[C@@H]3C=C(C)C4=CC(=O)CC[C@@]4(C)[C@H]3CC[C@]21C
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.