5-Carboxy-4-methyl-2-(pyrazin-2-yl)-1,3-thiazole2-(5-Carboxy-4-methyl-1,3-thiazol-2-yl)pyrazine4-Methyl-2-(pyrazin-2-yl)-1,3-thiazole-5-carboxylic acid4-methyl-2-(2-pyrazinyl)-1,3-thiazole-5-carboxylic acid4-Methyl-2-(2-pyrazinyl)thiazole-5-carboxylic acid2-(2-Pyrazinyl)-4-methylthiazole-5-carboxylic acid4-甲基-2-(2-吡嗪基)噻唑-5-羧酸