COC(=O)C(Cc1c[nH]c2ccccc12)NP(=O)(O)OCC1OC(n2ccc(N)nc2=O)C(O)C1O
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?