In this work, new phosphoramidates were prepared and screened for their putative urease inhibitory activity. The importance of this class of compounds is related to the wide range of biological activities which they exhibit. Consequently, higher activity shown by phosphoramidates 3a, 4b, 5a, 5b, 5c, and 9a suggests that they could serve as lead substances for the development of novel synthetic compounds with enhanced inhibitory ureolitic activity. Their predicted ADMET properties are also in accordance with the general requirements for drug-like compounds. Structure–activity relationship analyses suggest that the presence of cyclohexylamine group is an important structural feature associated with enhanced activities. DFT calculations were performed to obtain the energy values of HOMO and LUMO, and dipole moment.