In this study beta-lactam derivatives which include 1,3,4-thiadiazole and 1,3,4-oxadiazole structure (8a,b) have been achieved by cyclocondensation reaction. The synthesized compounds were investigated for antioxidant capacity and in vitro antiurease activity. The obtained compounds displayed good-moderate urease inhibiton results in comparison with thiourea, standard drug. Also, frontier molecular orbital analysis, reactivity descriptors (such as ionization energy (I), electron affinity(A), electro negativity(chi), chemical hardnesses (eta) and chemical softness (S), chemical potential (mu) and global electrophilicity index (omega)), nonlinear optical properties (NLO) and molecular electrostatic potential (MEP) studied with DFT approach and B3LYP/6-311++G (d,p) level of theory. Nonlinear optical calculations presented that 7b and 8b have very large nonlinear optical activity. In addition, molecular docking studies were performed. (C) 2020 Elsevier B.V. All rights reserved.