4-(Difluoromethyl)-3-nitro-6-(trifluoromethoxy)pyridine-2-carboxamide
5-(Difluoromethyl)-2-nitro-3-(trifluoromethoxy)pyridine-6-carboxamide
4-(Difluoromethyl)-3-nitro-5-(trifluoromethoxy)pyridine-2-carboxamide
4-(Difluoromethyl)-5-nitro-2-(trifluoromethoxy)pyridine-3-carboxamide