Targeted Synthesis and Analysis of Biologically Active Azomethine Derivatives of 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxamide

Abstract

Introduction. Azomethine derivatives of 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxamide are acyclic precursors of biologically active compounds derived from 5,6,7,8-tetrahydro-3H-benzoteopheno[2,3-d]pyrimidine-4-one. Examples of these groups of compounds with different pharmacological properties are given in the literature, but their cytostatic effect is mainly described. These data and the preparative availability allow us to judge the prospects for further study and molecular design in a number of azomethine derivatives of 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxamide. Optimization of methods for the synthesis and analysis of substances of this series and the identification of structure-activity relationship are of considerable interest for medical chemistry and pharmaceutical science. The resulting leading compounds will allow us to further develop laboratory requirements for the synthesis of an active pharmaceutical substance.Aim. To make a predict, optimize the synthesis conditions and develop a method for high performance liquid chromatography (HPLC) analysis of pharmacologically active azomethine derivatives of 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxamide.Materials and methods. The prediction of biological activity was carried out through the web resource PASS Online. The synthesis of the target azomethines was carried out by the interaction of aromatic aldehydes with 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxamide in an ethanol. The reaction was monitored by thin-layer chromatography (TLC). The determination of related impurities was done by HPLC. The analysis was carried out under the conditions of isocratic elution with a mobile phase of acetonitrile – water (70:30).Results and discussion. The results of the prediction of the biological activity of the constructed structures suggest the manifestation of cytostatic, antitubercular and anti-inflammatory activity characteristic of all target azomethines. The analysis of the reactivity revealed the influence of substituents of aldehydes contained in the aromatic core on the completeness of the condensation reaction. The spectral characteristics clearly confirmed the structure of the products, and the HPLC results showed the purity of the obtained substances, which is more than 95 %.Conclusion. As a result of the conducted studies, the structure of promising azomethine derivatives of 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxamide was justified and the method of their synthesis and analysis by HPLC was optimized. In the future, the results of the research will allow us to identify the leading compounds with the specified pharmacological properties.