Synthesis and Biological Evaluation of Novel Glycosyl-Containing 1,2,4-Triazolo[3,4-b][1,3,4]Thiadiazole Derivatives as Acetylcholinesterase Inhibitors

An efficient protocol for the synthesis of novel glycosyl-containing 1,2,4-triazolo[3,4- b][1,3,4]thiadiazole derivatives starting from the commercially available D-glucosamine hydrochloride is described by reaction of glycosyl isothiocyanate with various aminotriazoles in DMF. Glycosyl isothiocyanate is an important intermediate and synthetic methods are discussed. The acetylcholinesterase inhibitory activity of these compounds was tested by Ellman's method. It was found that most compounds exhibited over 90% inhibition and they were subsequently evaluated for their IC50 values.