5-methoxycarbonyl-2-methylpyrazole-3-carboxylic acid

1H-吡唑-3,5-二甲酰氯

4,9-dioxo-4H,9H-dipyrazolo[1,5-a,1',5'-d]pyrazine-2,7-dicarboxylic acid

4-Nitro-1H-pyrazole-3,5-dicarboxylic acid