A novel biologically active selenoorganic compound. VIII. Biotransformation of ebselen.

1. The metabolism of ebselen, a Se-containing heterocyclic compound, in rats, pigs and human volunteers has been investigated. 2. Unchanged ebselen is not present in urine, plasma or bile. All metabolites of ebselen have in common that the isoselenazolone ring is opened. 3. Both in pigs and human, the dominant metabolite in plasma and urine is a Se-glucuronide. This is the major metabolite in rats as well but, additionally, some selenomethyl-derivatives of ebselen can be detected.