CO[C@@]1(NC(=O)Cc2cccs2)C(=O)N2C(C(=O)O)=C(COC(N)=O)CS[C@@H]21 represents a molecule that is penetrating the blood brain barrier to reach the brain.
{SMILES#} represents a molecule that is {penetrate_BBB#not &NULL}{penetrate_BBB__names__adjective}.