Abstract

Background: 2-aminoselenazoles became an important core in medicinal chemistry after the discovery of Ebselen and Ethaselen. Therefore, many researchers have reported the synthesis of small selenazole intermediates via Hantzsch cyclization using a wide array of methodologies and catalysts.

Methods: In this work, we investigated the formation of 2-aminoselenazoles on various organic solvents and in water, under catalyst-free conditions. Moreover, these molecules and their 2-aminothiazoles analogues were assessed in vitro for their antitubercular activity against Mycobacterium tuberculosis and the results compared.

Results: Instant reactions were observed when using polar aprotic solvents and all selenazoles were synthesized in water using sonochemistry. Furthermore, two selenazoles and one thiazole displayed activity in the µM range and the selenium heterocycles seems to be more potent than their sulphur analogues.

Conclusion: This is the first study of selenazoles against M. tuberculosis. It is noteworthy that 2-amino-1,3-selenazoles are interesting synthetic intermediates that could be incorporated into novel prototypes against tuberculosis.

Keywords: Tuberculosis, selenazole, synthesis, methodology, ultrasound, hantzsch cyclization.

Graphical Abstract