Novel 1-morpholine-3-substituted triazol-5-ones: Synthesis and multi-biological evaluation on HepG2 and U87 cells with SAR and DFT studies

• A novel series of 1-morpholine-3-substituted triazol-5-one derivatives was synthesized via a concise and efficient synthetic route. • The synthesized compounds were evaluated for cytotoxic effects against HepG2 (liver cancer) and U87 (glioblastoma) cell lines. • Structure–activity relationship (SAsR) analysis revealed key functional groups influencing biological activity. • Density Functional Theory (DFT) studies supported the electronic and geometric properties correlating with observed activities. • Certain derivatives demonstrated promising multi-target biological potential, indicating their value for further anticancer drug development. The biologically active novel 1-morpholine-3-substitue-4-(4-phenylacetoxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones 4(a-f) were successfully synthesized and structurally characterized by 1 H / 13 C NMR, and FT-IR spectroscopy. Concentration ranges of 31.25, 62.5, 125, 250, and 500 µg/mL were applied to determine the anti-cancer properties of compund. Significant results were obtained against the human hepatoma cells HepG2 and human glioblastoma cell line U87. Antioxidant activities were assessed in vitro using DPPH radical scavenging and metal chelation assays and it was seen that compounds 4(a-f) had metal chelating properties. Furthermore, the enzyme inhibitory effect of compounds on α-amylase (α-Amy), α-glucosidase (α-Gly), glutathione S-transferase (GST), acetylcholinesterase (AChE) enzymes were studied. IC 50 values were calculated in different ranges. The antimicrobial properties were investigated using the Agar-well diffusion technique. The compounds had antimicrobial activity against 5 bacteria except Escherichia coli, and especially the inhibition zone diameter of compound 4e against Bacillus cereus was found to be the highest with a measurement of 24 mm. Complementary density functional theory (DFT) calculations and structure-activity relationship (SAR) analyses were performed to provide insights into the molecular properties and biological activities of the synthesized Mannich bases.