CC(=O)O[C@H]1CC[C@@H](OC(C)=O)[C@H]2[C@H](O)[C@H](O)[C@@H]1n1c(=O)n(-c3ccccc3)c(=O)n12
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?