Synthetic aspects and first-time assessment of 2-amino-1,3-selenazoles against Mycobacterium tuberculosis

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 mu M 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.