问题 单项选择题

对乙酰氨基酚的毒性代谢物是

A.对氨基酚

B.N-乙酰基亚胺醌

C.对乙酰氨基酚硫酸酯

D.对乙酰氨基酚葡萄糖醛酸结合物

E.对苯二酚

答案

参考答案:B

解析: 本题考查对乙酰氨基酚的代谢物。 对乙酰氨基酚在体内代谢时,会有少量生成N-羟基乙酰氨基酚,经进一步转化成毒性代谢物N-乙酰基亚胺醌,引起肝脏毒性和致癌性,A项为干扰项,对氨基酚毒性较大,是合成过程中乙酰化不完全或贮藏过程中水解引入的杂质,非代谢产物,故本题选B。

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