Novel synthesis of a new class of substituted <i>S-</i> glycosylisothiourea derivatives and their conversion to 5-amino-1,2,4-triazoles

Abstract

The one-pot reaction of potassium cyanocarbamimidothiolates with acetylated bromo sugars produced a novel class of substituted glycosylisothiourea derivatives 5a–h that demonstrated their Z-configuration. Some of the later compounds 5a–d were treated with NH3 in methanol at 25 °C, to afford the unprotected thioglycoside functionalized compounds 6a–c with excellent yields. To characterize the structure of the newly synthesized compounds, various techniques, such as elemental analysis and spectral data (13C NMR, IR, and 1H NMR) were employed. Furthermore, the substituted S-glycosylisothioureas 5 and 6 were subjected to a reaction with hydrazine hydrate, resulting in the formation of corresponding 5-amino-1,2,4-triazole derivatives 7a–d. The antibacterial properties of all newly synthesized compounds were thoroughly assessed and evaluated. Among these compounds, the most potent antimicrobial agents were found to be compounds 5a, 5g, 6a, 6b, and 6c.