CC(C)OP(=O)(OC(C)C)C1=NN(c2ccc([N+](=O)[O-])cc2)C(P(=O)(OC(C)C)OC(C)C)=NN1c1ccc([N+](=O)[O-])cc1
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?