Characterization of urinary metabolites of a new benzofuroquinoline derivative, 3,9-bis(N,N-dimethylcarbamoyloxy)-5 H-benzofuro[3,2-c]-quinoline-6-one (KCA-098), in dogs.

The metabolism of 3,9-bis(N,N-dimethylcarbamoyloxy)-5 H-benzofuro[3,2-c]-quinoline-6-one (KCA-098), a new inhibitor of bone resorption and stimulator of bone formation, was examined after oral administration to dogs. Nine metabolites and the unchanged KCA-098 were isolated by extraction and HPLC from dog urine. The structures of these metabolites were characterized by LC/MS or LC/MS/MS, and/or were confirmed by comparison with corresponding authentic standards. The presumed main metabolic pathways were hydrolysis, hydroxylation, and N-demethylation of the N,N-dimethyl-carbamate ester group.