CC(=O)OCC1OC(n2c(=O)n(-c3ccccc3)c(=O)c3cc(Br)cc(Br)c32)C(OC(C)=O)C(OC(C)=O)C1OC(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.