Synthesis and Antimicrobial Activity of Phenylthioand Benzylsulfonylacetic Acids Based on 2-amino-5-alkyl(arylalkyl)-1,3,4-thiadiazoles

Several 2-amino-5-alkyl-1,3,4-thiadiazole derivatives are known to be biologically active [1 – 3]. However, 2-amino-5-alkyl-1,3,4-thiadiazole amides based on phenylmercaptoacetic and benzylsulfonylacetic acids have not previously been studied. The possible activity of such structures was mentioned [4] although the compounds themselves were not synthesized. Therefore, we prepared Ia-f and IIa-d and studied their antimicrobial activity. Reactions of 2-amino-5-alkyl(arylalkyl)-1,3,4-thiadiazole with phenylthioacetic acid chloride and of 2-amino-5alkyl-1,3,4-thiadiazole with benzylsulfonylacetic acid chloride produced the corresponding N-(5-alkyl-1,3,4-thiadiazol2-yl)-2-(phenylthio)acetamides (I) and 2-(benzylsulfonyl)N-(5-alkyl-1,3,4-thiadiazol-2-yl)acetamides (II) (Scheme 1).