2-cyano-3-(2-methoxycarbonyl-phenyl)-3-oxo-propionic acid ethyl ester

2,2-di-p-tolyl-propionic acid

2-(3-methylbut-2-enyl)propanedioic acid

左旋多巴

4-hydroxy-6-methyl-isophthalic acid-1-ethyl ester