Kucukbay, HasanGonul, ZeynepKucukbay, Fatumetuzzehra ZehraTekin, ZehraAngeli, AndreaBartolucci, GianlucaSupuran, Claudiu T.2024-08-042024-08-0420210365-62331521-4184https://doi.org/10.1002/ardp.202100122https://hdl.handle.net/11616/100063Six new monopeptides, seven new dipeptides, and two deprotected monopeptide dihydroquinolinone conjugates were prepared by the benzothiazole-mediated method and their structures were confirmed by nuclear magnetic resonance, mass, infrared spectroscopy, and elemental analysis methods. The human carbonic anhydrase (hCA) I and hCA II enzyme inhibition activities of the compounds were determined using the stopped-flow instrument. The synthesized peptide-dihydroquinolinone conjugates 2, 3, 6, 10, 13, and 15 showed inhibition against the hCA II enzyme in the range of 15.7-65.7 mu M. However, none of the compounds showed inhibition of hCA I at a concentration of 100 mu M. The antioxidant activities of the compounds were also examined using the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging method at concentrations of 12.5-125 mu g/ml, but when compared with the standard antioxidant compounds alpha-tocopherol and butylated hydroxyanisole (BHA), weak antioxidant activities were detected. The cytotoxic effects of four compounds against the A549 and BEAS-2B cell lines were also investigated. Among the compounds studied, compound 7 was found to be most effective, with the IC50 values on the A549 cells for 48 and 72 h being 26.87 and 9.979 mu g/ml, respectively, and the IC50 values on the BEAS-2B cells being >100 mu g/ml. None of the tested compounds showed antimicrobial activity in the concentration range (800-1.56 mu g/ml) studied.eninfo:eu-repo/semantics/closedAccessantioxidantcarbonic anhydrasecytotoxicitypeptidepeptide-dihydroquinolin-2-one conjugatesquinolonesArticle354113431332410.1002/ardp.2021001222-s2.0-85111095877Q2WOS:000677723600001Q2