5-Hydroxy-2-nitro-3-(trifluoromethoxy)pyridine-4-carboxaldehyde
6-(Difluoromethyl)-3-hydroxy-4-(trifluoromethoxy)-2-(trifluoromethyl)pyridine
5-Hydroxy-4-nitro-2-(trifluoromethoxy)pyridine-3-carboxaldehyde
4-Hydroxy-5-nitro-3-(trifluoromethoxy)pyridine-2-carboxaldehyde