['CCCN', 'Cc1noc(C)c1CNC=O', 'CCCNC=O', 'Cc1noc(C)c1CN', 'CCC', 'Cc1noc(C)c1CNC(N)=O', 'CCCNC(N)=O', 'Cc1noc(C)c1C', 'Cc1cc(C)on1', 'CCCNC(=O)NC']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1cnoc1.