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