A novel and innovative compound, 2-amino-5-S-benzyl-1, 3, 4-thiadiazole (ABMT) was prepared from 2-amino-5-mercapto-l, 3, 4-thiadiazole ( AMT); the assigned structure was based on spectral analysis. The activity of this compound showed pronounced antitumor activity that was confirmed from reversible redox characteristic and quantum chemical calculations. The computational evidence for the antitumor activity was obtained via the performed molecular modeling of ABMT using Gaussian 09 system. The optimal geometries of molecular skeleton and molecular orbital (MO) densities were visualized using the corresponding Gauss View software. The ABMT compound was simulated with TD-DFT method in polarizable continuum solvent model PCM of methylene chloride. The optimized geometry of the molecular skeleton and the molecular orbital (MO) densities were visualized. The stability of ABMT in aqueous solutions at pH 1.2, 6.8 and 7.4 simulating the body fluids: stomach, intestine and blood respectively was investigated using High Performance Liquid Chromatography (HPLC). The prepared compound is relatively stable and showed the best performance at pH 7.4.