COc1ccc2[nH]c3c(c2c1)CCN1C(=O)C(CC(=O)NCc2cccc(C(F)(F)F)c2)C[C@H](C(=O)N2CCCCC2)[C@@]31C
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.