Development and Validation of HPLC Determination of related Substances in A Novel Anticonvulsant agent Epimidin

Abstract

1-(4-methoxyphenyl)-5-[2-[4-(4-methoxyphenyl)piperazin-1-yl]-2-oxo-ethyl]pyrazolo[3,4-d]pyrimidin-4-one has been reported as a promising new anticonvulsant drug candidate with a code name “Epimidin”. A new HPLC method for the related substances determination of potential active pharmaceutical ingredient has been developed and validated. The method uses ACE C18 column (250x4.6mm, 5µm) and gradient elution. Mobile phase consisted of a mixture of methanol R (mobile phase A) and phosphate buffer solution with triethanolamine, adjusted to pH 7.0 (mobile phase B). During the analysis, the ratio of mobile phases was changing according to a gradient mode at a flow rate of 1ml/min. The DAD detection was set at 240nm. The method was validated according to the ICH guidelines and requirements of State Pharmacopoeia of Ukraine. Drug substance was thoroughly explored for stability assessments under various stress conditions such as high temperature, as well as the influence of strong acid and base and oxidizing agents. The obtained solutions were analyzed by HPLC and LC/MS. It has been shown that the substance Epimidin was not resistant to the action of peroxide, alkali and acid decomposition – the mentioned stress conditions lead to the formation of unidentified impurities.