This study involves a synthesis of some formazan derivatives starting from react chloro acetyl chlorid with 2-amino-4-hydroxy-6-methyl pyrimidine to gate compound (a), (a) react with hydrazine hydrate to give compound (b) also (b) react with 3-4-dimethoxy benzaldehyd to product Schiff base derivative (c) then (c) react with deferent amin derivatives to get formazan derivatives. All these compounds characterized by 13C-NMR, fourier transform infrared spectroscopy (FTIR), 1HMNR. After that, we study the biological activity for all formazan derivatives toward two different kinds of bacteria and anti-cancer.