Reactivity of 2-amino-1,3,4-thiadiazoles. Methylation reactions of some 2-amino-5-benzoyl-1,3,4-thiadiazoles

Methylation reactions of 2-amino-5-benzoyl-1,3,4-thiadiazoles 1a-d are reported as a function of alkylating agents (methyl iodide, dimethyl sulfate-potassium carbonate, diazomethane, dimethyl-sulfate-sodium methoxide). Methylation occurs at both the ring nitrogen in position 3 and the exocyclic nitrogen atom.