CC(=O)O.CC(=O)OC[C@H]1O[C@@H](Oc2cc3ccc(=O)oc3cc2OC(C)=O)[C@H](OC(C)=O)[C@@H](OC(C)=O)[C@@H]1OC(C)=O
PSA is a commonly used medicinal chemistry metric for the optimization of a drug's ability to permeate cells. Please predict psa of this molecule.