Abstract Features of electrophilic and nucleophilic substitution under chlorination and nitration reactions conditions have been investigated for 6-hydroxy-and 6-methyl-substituted derivatives of 3-cyano-4-methyl-2 (1H)-pyridones. The polychloro-and nitro-substituted 3- cyano-4-methylpyridines obtained were used as synthons in the synthesis of some polyhalo- and nitro-substituted nicotinic acids and their amides. The fragmentation pathways of the ...