Cc1nc(Nc2cnc(/C=C/c3cc(C(=O)Nc4cccc(C(F)(F)F)c4)ccc3C)cn2)cc(N2CCNCC2)n1.O=C(O)C(F)(F)F
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.