O=C(OCC(OC(=O)c1ccccc1)C(OC(=O)c1ccccc1)C(OC(=O)c1ccccc1)c1cnn(-c2ccccc2)n1)c1ccccc1
Molecules with a polar surface area of greater than 60 angstroms squared (Å2) is hard to pass brain blood barrier. What's the psa of this molecule?