New compounds derived from N-phthalyl DL-leucine as amino acid derivative and some kinds of sulfa drugs like sulfanilamide, sulfaisoxazole, sulfamethaxzole, sulfadiazine, sulfathaizole, sulfapyridine and sulfacetamide sodium were prepared by utilizing N, N-Dicyclohexylcarbodimide (DCCI) as condensing agent to promoted condensation reaction to appointed the corresponding amide. All the synthesized compounds have been characterizated by elemental analysis (C, H, N, S), FT-IR and H NMR. The antimicrobial activity of these compounds were determined against two kinds of bacteria gram positive (Staphylococcus aures) and gram negative (Aerompanas veronil) by using different concentration of each synthesized compound in addition the MIC was determined.