['Cc1ccc(CC=O)cc1', 'COCCNC(=O)NC(=O)CO', 'COCCN', 'Cc1ccc(CC(=O)OCC(=O)NC=O)cc1', 'COCCNC=O', 'Cc1ccc(CC(=O)OCC(N)=O)cc1', 'COCCNC(N)=O', 'Cc1ccc(CC(=O)OCC=O)cc1', 'CO', 'CCNC(=O)NC(=O)COC(=O)Cc1ccc(C)cc1', 'Cc1ccc(CC(=O)O)cc1', 'COCCNC(=O)NC(C)=O', 'CCOC', 'Cc1ccc(CC(=O)OCC(=O)NC(N)=O)cc1', 'Cc1ccccc1', 'COCCNC(=O)NC(=O)COC(C)=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.