Using Nc1cccnc1, Cc1ccc(CNc2ccc3c(C=O)cccc3n2)o1 to produce Cc1ccc(CNc2ccc3c(CNc4cccnc4)cccc3n2)o1, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.