Ethyl 6-hydroxy-2-nitro-3-(trifluoromethoxy)pyridine-4-carboxylate
Methyl 3-hydroxy-2-methoxy-6-(trifluoromethoxy)pyridine-5-carboxylate
Ethyl 2-hydroxy-6-nitro-4-(trifluoromethoxy)pyridine-3-carboxylate
Methyl 3-hydroxy-2-methoxy-5-(trifluoromethoxy)pyridine-4-carboxylate