Abstract
The metabolism of azuletil sodium (AZE, KT1-32, sodium 3-ethyl-7-isopropyl-l-azulenesulfonate 1/3hydrate), a novel anti-ulcer agent, was studied after oral administration of 14C-KT1-32 to male rats. The intact KT1-32 and six metabolites were found in the urine of male rats and were identified by high performance liquid chromatography (HPLC) using a radioisotope detector. The sum of radioactivities of these identified metabolites accounted for 94% of the total radioactivity in the urine. These metabolites were isolated by various solid extraction cartridges. The structural elucidation of the isolated metabolites was carried out by 1H-NMR spectroscopy and mass spectrometry with electron ionization mode after converted them into the n-propylester-dimethyl ethylsilyl ether derivatives, especially mass spectrometry was very useful to characterize each of these metabolites. M3, only one conjugate, was found to be as the sulfate of the ω-1 hydroxylated metabolite of the ethyl group in KT 1-32. All of these metabolites, except M3, were identified by the comparison of their spectral data with those of the authentic compounds, indicating that the preferential ω-1 hydroxylations of KT1-32 took place on the alkyl groups in 3 and 7 positions and did not on the azulene ring itself.
