67-56-1
甲醇
+
2860-55-1
6-methyl-2-oxo-1H-pyridine-3,4-dicarboxylic acid
→
82140-59-8
dimethyl 2-chloro-6-methylpyridine-3,4-dicarboxylate
82140-73-6
2-chloro-4-methoxycarbonyl-6-methylpyridine-3-carboxylic acid