COC1=N[C@H](C(C)C)C(OC)=N[C@H]1Cc1ccc(C[C@@H]2N=C(OC)[C@@H](C(C)C)N=C2OC)s1
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?