['CCN', 'C[C@@H](C(=O)NC=O)N(C)Cc1ccccc1[N+](=O)[O-]', 'CCNC=O', 'C[C@@H](C(N)=O)N(C)Cc1ccccc1[N+](=O)[O-]', 'CCNC(N)=O', 'C[C@@H](C=O)N(C)Cc1ccccc1[N+](=O)[O-]', 'CC', 'C[C@@H](C(=O)NC(N)=O)N(C)Cc1ccccc1[N+](=O)[O-]', 'CCNC(=O)NC(=O)CC', 'CNCc1ccccc1[N+](=O)[O-]', 'Cc1ccccc1[N+](=O)[O-]', 'CCNC(=O)NC(=O)[C@H](C)NC', 'O=[N+]([O-])c1ccccc1', 'CCNC(=O)NC(=O)[C@H](C)N(C)C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.