['NC=O', 'CC(C)[C@@H](N)C(=O)N1CCN(c2cccc(Cl)c2)CC1', 'CC(C)[C@H](C=O)NC(N)=O', 'Clc1cccc(N2CCNCC2)c1', 'NC(N)=O', 'CC(C)CC(=O)N1CCN(c2cccc(Cl)c2)CC1', 'Clc1ccccc1', 'CC(C)[C@@H](NC(N)=O)C(=O)N1CCNCC1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc(N2CCNCC2)cc1.