CCCC(=O)c1c(NOC2OC(COC(C)=O)C(OC(C)=O)C(OC(C)=O)C2OC(C)=O)nc(OC)n(C)c1=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.