Ethyl 2,6-dihydroxy-3-(trifluoromethoxy)pyridine-5-carboxylate
Ethyl 3,6-dihydroxy-2-(trifluoromethoxy)pyridine-4-carboxylate
Ethyl 2,4-dihydroxy-6-(trifluoromethoxy)pyridine-3-carboxylate
Methyl 3,5-dihydroxy-2-(trifluoromethoxy)pyridine-6-carboxylate