['CO', 'CNC(=O)c1sc(N)c(C=O)c1CBr', 'CN', 'COC(=O)c1c(N)sc(C=O)c1CBr', 'CNC=O', 'COC(=O)c1c(CBr)csc1N', 'COC=O', 'CNC(=O)c1sc(N)cc1CBr', 'CBr', 'CNC(=O)c1cc(C(=O)OC)c(N)s1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccsc1.