O=C(Nc1ncnc2c1ncn2[C@@H]1O[C@H](/C=C/C(=O)N2CCN(c3ccc(F)cc3)CC2)[C@@H](O)[C@H]1O)c1ccccc1
Molecules with a polar surface area of greater than 140 angstroms squared (Å2) tend to be poor at permeating cell membranes. What's the psa of this molecule?