THE CHEMISTRY OF PHOSPHORAMIDATES WITH C (O) NHP (O) MOIETY HAS RECEIVED CONSIDERABLE ATTENTION FROM THE PERSPECTIVE OF SYNTHESIS, STEREOCHEMISTRY, COORDINATION CHEMISTRY, XRAY CRYSTALLOGRAPHY, AND THEORETICAL STUDIES [1, 2].THE PRESENCE OF THESE FUNCTIONALITY IN THESE COMPOUNDS NOT ONLY CAUSES DIVERSE BIOLOGICAL ACTIVITIES, BUT ALSO MAKES DIFFERENT CONFORMATIONS OF P (O) VERSUS C (O) IN THIS SKELETON. ON THE OTHER HAND, AMMONIUM SALTS PLAY VITAL BIOLOGICAL ROLES AS ANTIMICROBIAL AGENTS, FUNGICIDES, AND PESTICIDES [3]. THE SYNTHESIS AND STRUCTURE OF AMMONIUM DICHLOROPHOSPHATE AND PYRIDINIUM DIHYDROGEN PHOSPHATE HAVE ALSO BEEN REPORTED, WHEREAS AMMONIUM PHOSPHATES BEARING PEPTIDE MOIETY ARE RARE IN THE RELEVANT STUDIES [4]. HOWEVER, IN THE PRESENT WORK, WE PREPARED FIVE NEW BENZYLAMMONIUM PHOSPHINATES WITH FORMULA [XC6H4NHC (O) NHP (O) YO]-[H2Y]+(Y=N (CH3) (CH2C6H5), X=H (1), CH3 (2), NO2 (3); Y=NH (CH2C6H5), X=H (4), NO2 (5)) AND CHARACTERIZED BY IR, 1HNMR, 13CNMR AND 31PNMR SPECTROSCOPY. ON THE BASIS OF OUR KNOWLEDGE, THE REACTION OF AMINES WITH PHOSPHORAMIDIC DICHLORIDES IN THE PRESENCE OF THE HCL SCAVENGER IS A METHOD FOR THE FORMATION OF PHOSPHORAMIDATES, WHEREAS, WE PREPARED NEW BENZYLAMMONIUM PHOSPHINATES, PROBABLY AS A CONSEQUENCE OF HYDROLYSIS OF STARTING PHOSPHORAMIDIC DICHLORIDES IN THE COURSE OF THE REACTION. ALSO, THEIR ANTIMICROBIAL ACTIVITY TESTED BY USING CUP-PLATE AGAR AND MIC METHODS. EVALUATION OF THE BIOLOGICAL ACTIVITY REVEALED THAT ONLY TWO COMPOUNDS (1 AND 5) WERE ACTIVE AGAINST B. SUBTILISAND ONLY 1 WAS ACTIVE AGAINST P. AERUGINOSA. COMPOUNDS 1 - 5 ARE COMPLETELY INACTIVE AGAINSTE. COLI, S. AUREUS, A. NIGER, AND C. ALBICANS.