2-溴-4-吡啶羧酸英文名称:2-Bromopyridine-4-carboxylic acidCAS号:66572-56-3分子式:C6H4BrNO2分子量:202.012-氯-5-硝基吡啶英文名称:2-Chloro-5-nitropyridineCAS号:4548-45-2分子式:C5H3ClN2O2分子量:158.54