1992 Volume 7 Issue 6 Pages 799-812
The metabolism of ME1207, a new oral esterified cephem of ME1206, was studied in rats and dogs.
When ME1207 was administered orally to rats, the ME1207 was isomerized slightly to ME 1207E and ME1207Δ3 in gastro-intestinal tract. The ME1206E and ME1206Δ3 were found in the plasma in trace amount in addition to ME1206, the main compound, after oral administration of ME1207. We assumed that these isomers of ME1206 originated from those of ME1207, formed in the gastro-intestinal tract.
The metabolites in the urine and feces after oral administration of (Aminothiazole-2-14C) ME1207 to rats and dogs were analyzed by radio-HPLC. ME1206 was mainly excreted in the urine in rats and dogs. MOH, the degraded product which is formed by the opening of the β-lactam ring of ME1206, was mainly excreted in the feces in rats. On the other hand, ME 1206, ME1207, ME1206E, ME1206Δ3 and MOH were excreted in the feces in dogs.
Pivalic acid, the metabolite derived from the ester moiety of ME1207, was detected in the urine in a form of conjugate after oral administration of ME1207 to rats and dogs. Its urinary excretion ratio within 48hr was 58.17% and 50.68% of administered dose in rats and dogs, repectivly.
