In vitro sulfonation of 7-hydroxycoumarin derivatives in liver cytosol of human and six animal species

Sulfonation is an important high affinity elimination pathway for phenolic compounds.In this study sulfonation of 7-hydroxycoumarin and 13 its derivatives were evaluated in liver cytosols of human and six animal species. 7-hydroxycoumarin and its derivatives are strongly fluorescent, and their sulfate conjugates are nonfluorescent at excitation 405 nm and emission 460 nm. A convenient fluorescence based kinetic assay of sulfonation was established.The sulfonation rate of most of the 7-hydroxycoumarin derivatives was low in liver cytosol of human and pig, whereas it was high with most compounds in dog and intermediate in rat, mouse, rabbit, and sheep. Sulfonation of the 7-hydroxycoumarin der…