Preclinical evaluation of 1,2,4-triazole-based compounds targeting voltage-gated sodium channels (VGSCs) as promising anticonvulsant drug candidates

Epilepsy is a chronic neurological disorder affecting nearly 65–70 million people worldwide. Despite the observed advances in the development of new antiepileptic drugs (AEDs), still about 30-40% of patients cannot achieve a satisfactory seizure control. In our current research, we aimed at using the combined results of radioligand binding experiments, PAMPA-BBB assay and animal experimentations in order to design a group of compounds that exhibit broad spectrum of anticonvulsant activity. The synthesized 4-alkyl-5-substituted-1,2,4-triazole-3-thione derivatives were primarily screened in the maximal electroshock-induced seizure (MES) test in mice. Next, the most promising compounds (17, 22) were investigated in 6 Hz (32 mA) psychomotor seizure model. Protective effect of compound 22 was almost similar to that of levetiracetam. Moreover, these compounds did not induce genotoxic and hemolytic changes in human cells as well as they were characterized by low cellular toxicity. Taking into account the structural requirements for good anticonvulsant activity of 4-alkyl-5-aryl-1,2,4-triazole-3-thiones, it is visible that small electron-withdrawing substituents attached to phenyl ring have beneficial effects both on affinity towards VGSCs and protective activity in the animal models of epilepsy

Radiation Sterilization of Anthracycline Antibiotics in Solid State

The impact of ionizing radiation generated by a beam of electrons of 25–400 kGy on the stability of such analogs of anthracycline antibiotics as daunorubicin (DAU), doxorubicin (DOX), and epidoxorubicin (EPI) was studied. Based on EPR results, it was established that unstable free radicals decay exponentially with the half-time of 4 days in DAU and DOX and 7 days in EPI after irradiation. Radiation-induced structural changes were analyzed with the use of spectrophotometric methods (UV-Vis and IR) and electron microscope imaging (SEM). A chromatographic method (HPLC-DAD) was applied to assess changes in the contents of the analogs in the presence of their impurities. The study showed that the structures of the analogs did not demonstrate any significant alterations at the end of the period necessary for the elimination of unstable free radicals. The separation of main substances and related substances (impurities and potential degradation products) allowed determining that no statistically significant changes in the content of particular active substances occurred and that their conversion due to the presence of free radicals resulting from exposure to an irradiation of 25 kGy (prescribed to ensure sterility) was not observed

Impact of hydrochlorothiazide on the stability of two perindopril salts. Evaluation of the interaction with HPLC and ESI LC/MS methods

Perindopril (PER) belongs to the group of the angiotensin converting enzyme inhibitors and is widely prescribed antihypertensive drug. It can be used in monotherapy or in combination therapy for example with hydrochlorothiazide (HTH). As on the market there is no pharmaceutical formulation containing both drugs and in literature has not been reported any work about effect of HTH on PER degradation process, the primary objective of this study was the assessment of stability of two salts of perindopril - tert-butylamine (PERt) and arginine (PERa) in a mixtures model with HTH in different relative humidities and constant temperature. Objective of the study was establishing the mechanisms of drug decomposition in the presence of HTH. Results were achieved using the high performance liquid chromatography (RP-HPLC). The degradation rate constants for mixtures and pure substances were calculated. Decomposition products have been analyzed by ESI LC/MS and the decomposition mechanism for each salt has been proposed. The degradation of PERt in the presence of HTH took place according to autocatalytic reaction kinetic mechanism, described mathematically by Prout-Tompkins equation, and the decomposition process leads to hydrolysis. HTH in the model mixture with PERa generates a first-order kinetic model of the decomposition reaction, and there are two main products of decomposition: product of hydrolysis and diketopiperazine. Our study showed that HTH has statistically significant positive impact on both salts. It can be suggested that PERt or PERa and HTH can be formulated together, hence there is no negative interaction between the drugs