O=C(CC1C[C@H](C(=O)N2CCCCC2)[C@@]2(CCc3ccccc3)c3[nH]c4ccccc4c3CCN2C1=O)NCCCn1ccnc1
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?