COc1cc(-c2c(C(C)=O)c(-c3ccccc3)n(C3OC(COC(C)=O)C(OC(C)=O)C(OC(C)=O)C3OC(C)=O)c(=S)c2C#N)ccc1O
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.