COc1ccc(O[C@H]2C=C[C@@H](c3ccccc3)O[C@H]2COC(=O)CC/C(C)=N\O[C@@H](C)c2cn([C@H]3COC[C@H]3O)nn2)cc1
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?