[Stability of 6-beta-[(hexahydro-1H-azepin-l-yl)methyleneamino]-penicillanic acid in aqueous solutions].

Stability of acqueous solutions of 6-beta-[(hexahydro-IH-azepin-I-yl)methylenamino] penicillanic acid at various values of pH and temperature was studied. It was found that inactivation of the antibiotic in both the acid and the alkaline medium proceeded according to the equation of the 1st order. At pH 1.3 and a temperature of 35 degrees the half life of the antibiotic was 7 hours. The activation energy calculated according to the Arrenius equation was 13.5 kcal/mol at pH 1.3 and 22.2 kcal/mol at pH 10.5. The antibiotic was inactivated in glycol and phosphate buffers. Its qualitative analysis was performed according to an improved iodometric method.