['CC(C)(C)O', 'NC[C@@H]1c2cccn2CCN1C=O', 'CC(C)(C)OC=O', 'NC[C@H]1NCCn2cccc21', 'CC(C)C', 'NC[C@@H]1c2cccn2CCN1C(=O)O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1cc2n(c1)CCNC2.