Mass spectrometric identification of urinary and plasma metabolites of 6-(6'-carboxyhexyl)-7-n-hexyl-1,3-diazaspiro-[4-4]-nonan-2,4-dione, a new cytoprotective agent.

The compound IBI-P-01028, or R,S-cis-6-(6'-carboxyhexyl)-7-trans-n-hexyl-1,3-diazaspiro-[4-4]-nona n-2,4- dione, is a new cytoprotective agent under development. To study the metabolites of this compound in laboratory animals, we administered it to dogs and rats, and analyzed extracts from dog and rat urine, and from dog plasma, by GC-MS. The metabolic profiles were different in the rat and dog. In the dog (plasma and urine), one metabolite was found, and in the rat urine two other metabolites were found. The unmetabolized drug was found only in the dog plasma and urine.