Synthesis of quinazolinone derivatives containing an acyl hydrazone skeleton as potent anti-urease agents enzyme kinetic studies and anti-oxidant properties

This paper covers the synthesis, in vitro urease inhibition, enzyme kinetic parameters, and anti-oxidant studies of a novel series of quinazolinone derivatives containing an acyl hydrazone skeleton. Compounds 3a, 3b, 5a, and 5b, having IC50 values ranging from 1.86 ± 0.07 to 6.38 ± 0.11 µg mL−1, show greater inhibitory activity than the standard inhibitor, thiourea. Among the products, (2-[2-(3-methoxybenzyl)-4-oxoquinazolin-3(4 H)-yl]acetohydrazide) proves to be the most potent, exhibiting enzyme inhibition activity with an IC50 value of 1.86 ± 0.07 µg mL−1. Kinetic studies involving the Lineweaver–Burk plots reveal that the inhibition mechanism of the most active compounds (3a, 3b, 5a, and 5b) on urease activity are found to be in competitive mode. Also, the anti-oxidant activity and radical-scavenging properties of the synthesized compounds are evaluated using cupric reducing anti-oxidant activity, ferric reducing anti-oxidant capacity, 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid), and 2,2-diphenyl-1-picrylhydrazyl assays. Compounds 3a, b and 5a, b have good anti-oxidant properties and radical-scavenging activity at various final concentrations.

Recent Efforts in the Discovery of Urease Inhibitor Identifications

Urease is an attractive drug target for designing anti-infective agents against pathogens such as Helicobacter pylori, Proteus mirabilis, and Ureaplasma urealyticum. In the past century, hundreds of medicinal chemists focused their efforts on explorations of urease inhibitors. Despite the FDA's approval of acetohydroxamic acid as a urease inhibitor for the treatment of struvite nephrolithiasis and the widespread use of N-(n-butyl)thiophosphoric triamide as a soil urease inhibitor as nitrogen fertilizer synergists in agriculture, urease inhibitors with high potency and safety are urgently needed. Exploration of novel urease inhibitors has therefore become a hot research topic recently. Herein, inhibitors identified worldwide from 2016 to 2021 have been reviewed. They structurally belong to more than 20 classes of compounds such as urea/thioure analogues, hydroxamic acids, sulfonamides, metal complexes, and triazoles. Some inhibitors showed excellent potency with IC50 values lower than 10 nM, having 10000-fold higher potency than the positive control thiourea.

Exploring biologically active hybrid pharmacophore N-substituted hydrazine-carbothioamides for urease inhibition: In vitro and in silico approach

Urease is potential target for various human's health complications, such as peptic ulcer, gastric cancer and kidney stone formation. The present study was based on synthesis of new hybrid pharmacophore N-substituted hydrazine-carbothioamides as potential urease inhibitors. Presented method gave excellent yield in range of 85-95% for hydrazine-carbothioamides derivatives (3a-s) after reaction of mono- and disubstituted hydrazides (1a-k) and substituted isothiocyanates (2a-d). All newly derivatives were characterized by advanced spectroscopic techniques (FTIR, ¹HNMR, ¹³CNMR, EMS) and were assessed for their urease inhibition potential. All analogs except for 3k, 3l and 3m demonstrated strong inhibitory potential for urease with IC₅₀ values of 8.45 ± 0.14 to 25.72 ± 0.23 μM as compared to standard thiourea (IC₅₀ 21.26 ± 0.35 μM). The structure-activity relationship and mode of interaction was established by molecular docking studies. It was revealed that the N-substituted hydrazine-carbothioamides interacted with nickel atoms present in the active site of urease and supported the correlations with the experimental findings. Therefore, the afforded hydrazine-carbothioamides derivatives are interesting hits for urease inhibition studies with future prospects of modification and optimization.

Antioxidant Activity of 1,2,4-Triazole and Its Derivatives: A Mini Review

The information about the presence of free radicals in biological materials was given for the first time about 70 years ago. Since then, numerous scientific studies have been conducted and the science of free radicals was born. Today we know that free radicals are by-products of enzymatic reactions occurring in the organism. They are produced during endogenous processes such as: cell respiration, phagocytosis, biosynthesis, catalysis, and biotransformation. They can also be produced by exogenous processes (radiation, sunlight, heavy metals, bacteria, fungi, protozoa and viruses). The overproduction of free radicals affects the aging processes, oxidative stress (OS) and takes part in the pathogenesis of various diseases. Among them are cancer, rheumatoid arthritis, neurodegenerative diseases: Alzheimer and Parkinson, pulmonary diseases, atherosclerosis and DNA damage. Compounds with antioxidant activity are very important nowadays because they allow organisms to keep a balance between the production of free radicals and the speed of their neutralization in the body. Next to the natural antioxidants (flavonoids, carotenoids, vitamins, etc.), synthetic ones are also of great importance. Among synthetic compounds with antioxidant activity are 1,2,4-triazoles and its derivatives. 1,2,4-Triazoles are heterocyclic compounds with three nitrogen atoms. Due to a broad spectrum of biological activities, these derivatives have been of interest to scientists for many years. Some of them are also used as drugs. The finding of new synthetic compounds with antioxidant features in the triazole group has become important problem of medicinal chemistry.