Thirteen novel hydrazone-Schiff bases (3-15) of fexofenadine were succesfully synthesized, structurally deduced and finally assessed their capability to inhibit urease enzyme (in vitro). In the series, six compounds 12 (IC50 = 10.19 ± 0.16 µM), 11 (IC50 = 15.05 ± 1.11 µM), 10 (IC50 = 17.01 ± 1.23 µM), 9 (IC50 = 17.22 ± 0.81 µM), 13 (IC50 = 19.31 ± 0.18 µM), and 14 (IC50 = 19.62 ± 0.21 µM) displayed strong inhibitory action better than the standard thiourea (IC50 = 21.14 ± 0.24 µM), while the remaining compounds displayed significant to less inhibition. LUMO and HOMO showed the transferring of charges from molecules to biological transfer and MEP map showed the chemically reactive zone appropriate for drug action are calculated using DFT. AIM charges, non-bonding orbitals, and ELF are also computed. The urease protein binding analysis benefited from the docking studies.