O=C(N[C@H]1CCCc2ccccc21)O[C@@H]1C(=O)c2cc(Br)ccc2O[C@H]1c1ccc2c(c1)OCO2
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?