3-(Difluoromethyl)-2-nitro-4-(trifluoromethyl)pyridine-5-acetic acid
2-(Difluoromethyl)-6-nitro-5-(trifluoromethyl)pyridine-3-acetic acid
2-(Difluoromethyl)-6-nitro-4-(trifluoromethyl)pyridine-3-acetic acid
6-(Difluoromethyl)-3-nitro-2-(trifluoromethyl)pyridine-4-acetic acid