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