The stability of the new chemical synthetic @entity61831 derivative (E118) was investigated using a stability-indicating high-performance liquid chromatography (HPLC) procedure. The examined samples were analyzed using a chiral HSA column and a mobile phase (pH 7.5) containing @entity69820 (5 mM), @entity5723 and 100 mM @entity10012 solution (1:9 v/v) at a flow rate of 1 ml min(-1). The developed method was specific, accurate and reproducible. The HPLC chromatograms exhibited well-resolved peaks of E118 and the degradation products at retention times <5 min. The stability of E118 was performed in 0.1 M @entity5836 , 0.1 M @entity7159 , water/ @entity1068 (1:1) and @entity1391 buffer (pH approximately 7.5) solutions. E118 was found to undergo fast hydrolysis in 0.1 M @entity5836 solution. The decomposition of E118 followed first order kinetics under the experimental conditions. The results confirmed that protonation of the @entity61831 system in the molecule enhanced the hydrolysis of E118 at degradation rate constant of 0.049 min(-1) and degradation half-life of 14.1 min at 25 degrees C. However, E118 was significantly stable in 0.1 M @entity7159 , physiological phosphate buffer (pH 7.5) and @entity1068 /water (1:1) solutions. The degradation rate constants and degradation half-lives were in the ranges 0.0023-0.0086 h(-1) and 80.6-150.6 h, respectively. Analysis of the acid-induced degraded solution of E118 by liquid chromatography-mass spectrometry (LC-MS) revealed at least two degradation products of E118 at m/z 213.1 and 113.1, respectively.

Stability study of the anticonvulsant XXXX (E118) using HPLC and LC-MS.

@entity69820 :: ('CHEBI:28837', 'Chemical') :: ['n-octanoic acid'] @entity5836 :: ('MESH:D006851', 'Chemical') :: ['hydrochloric acid'] @entity61831 :: ('CHEBI:51690', 'Chemical') :: ['enaminone'] @entity10012 :: ('CHEBI:34683', 'Chemical') :: ['disodium hydrogen phosphate'] @entity1391 :: ('CHEBI:26020', 'Chemical') :: ['phosphate'] @entity5723 :: ('MESH:D019840', 'Chemical') :: ['isopropyl alcohol'] @entity1068 :: ('MESH:D000431', 'Chemical') :: ['ethanol'] @entity7159 :: ('MESH:D012972', 'Chemical') :: ['sodium hydroxide']
@entity61831 :: (CHEBI:51690,Chemical) :: ['enaminone']
