Altretamine (hexamethylmelamine) is a chemotherapeutic agent used to treat advanced ovarian cancer. A simple one-pot synthesis procedure has been developed for the synthesis of altretamine under mild reaction condition. The preparation of atretamine has been performed by cyclotrimerization of dimethylcyanamide using tungsten and molybdenum hydrogen bronze as catalyst. These hydrogen bronzes are simply products obtained from hydrogen insertion into tungsten and molybdenum trioxides. The reaction was carried out in sealed culture tube at 150C and the products were characterized by using nuclear magnetic resonance (NMR), gas chromatography/mass spectrometric analysis (GC-MS) and, infrared spectroscopy (IR). The same reaction can be applied to methylthiocyanate.