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