he metabolic pathways of daidzein benzene sulfonate derivatives D1-D3 in human aortic vascular smooth muscle cells were studied in this paper.The cellular metabolites of daidzein benzene sulfonate derivatives were detected by HPLC-MS to infer the metabolic pathways in vitro of benzene sulfonate derivatives preliminarily.It was found that further glucuronidation and sulfation of the hydrolytic metabolites of daidzein benzene sulfonate derivatives D1-D3 were the main metabolic pathways,and there is a competition between these two reactions.The derivatives all could be metabolized to lead compound——daidzein(DD).The benzene sulfonate group of D2 underwent hydrolysis,followed by hydrolysis of methyl ether to form DD in the metabolic pathway.It indicated that the hydrolysis of phenylsulfonate bond was easier than that of methyl ether bond under the action of intracellular hydrolase.However,there were two possible metabolic pathways for compounds D1 and D3,which showed that acetyl,ethyl and benzenesulfonate groups could be hydrolyzed simultaneously under the action of intracellular hydrolase.This study on metabolism in vitro provided a reliable theoretical basis for the overall experiment of compounds D1-D3.