5-氯磺酰基-2-羟基苯甲酸 、 5-[(9H-Fluoren-9-ylmethoxycarbonylamino)-methyl]-pyrazine-2-carboxylic acid 、 alkaline earth salt of/the/ methylsulfuric acid 以3.2 mg的产率得到5-{[5-((S)-2-Carboxy-1-formyl-ethylcarbamoyl)-pyrazin-2-ylmethyl]-sulfamoyl}-2-hydroxy-benzoic acid