6-(Difluoromethyl)-3-fluoro-4-hydroxypyridine-2-sulfonyl chloride
2-(Difluoromethyl)-5-fluoro-4-methoxypyridine-3-sulfonyl chloride
2-(Difluoromethyl)-5-fluoro-3-hydroxypyridine-6-sulfonyl chloride
6-(Difluoromethyl)-4-fluoro-2-hydroxypyridine-3-sulfonyl chloride