One-pot Synthesis of 3,3,7,7-Tetramethyl- tetrahydro-[1,2,4]triazolo[1,2-a][1,2,4]triazole- 1,5-dithione and its Biological Activities

3,3,7,7-Tetramethyl-tetrahydro-[1,2,4]triazolo[1,2-a][1,2,4]triazole-1,5-dithione 1 has been synthesized from 2-chloropropionyl chloride ammonium thiocyanate, and hydrazine in 96% yield. Criss-cross cycloaddition involving aldazine produced from the acetone-hydrazine reaction was proposed for the mechanism. The structure was confirmed by micro-elemental analysis, FTIR, 1H and 13C NMR spectroscopy and ESI mass spectrometry. Compound 1 crystallized in monoclinic crystal system with P21/c space group. Antibacterial screening against Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis, and Gram-negative bacteria: Enterobacter aerogenes, Klebsiella pneumoniae, Proteus vulgaris, Escherichia coli, and Pseudomonas aeruginosa were conducted. The highest activity was against S. epidermidis (MIC = 1.563 mg/ml and MBC = 1.563 mg/ml) and Escherichia coli (MIC = 1.563 mg/ml and MBC = 1.563 mg/ml) thus exhibiting a moderate antibacterial activity.