Inhibition of the metalloenzyme urease has important pharmacologic applications in the field of antiulcer and antigastric cancer agents. Urease is involved in many serious infections caused by Helicobacter pylori in the gastric tract as well as by Proteus and related species in the urinary tract. Although numerous studies have described several novel urease inhibitors (UIs) used for the treatment of gastric and urinary infections, all these compounds have exhibited severe side effects, toxicity, and instability. Therefore, to overcome such problems, it is necessary to search for new sources of UIs, such as natural products, that provide reduced side effects, low toxicity, greater stability, and bioavailability. As limited studies have been conducted on plant-derived UIs, this paper aims to highlight and summarize the most promising compounds isolated and identified from plants, such as terpenoids, phenolic compounds, alkaloids, and other substances with inhibitory activities against plant and bacterial ureases; these are in vitro and in vivo studies with an emphasis on structure-activity relationship studies and types of inhibition that show high and promising levels of anti-urease activity. This will aid medicinal chemists in the design and synthesis of novel and pharmacologically potent UIs useful for the development of antiulcer drugs.

• Klíčová slova
• Antiulcer drugs, Bioactive compounds, Gastric and urinary infections, Herbal plants, Urease inhibitors,
• MeSH
• Bacteria enzymologie   MeSH
• lidé MeSH
• protivředové látky analýza   izolace a purifikace   farmakologie   MeSH
• rostliny enzymologie   MeSH
• ureasa antagonisté a inhibitory   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• protivředové látky MeSH
• ureasa MeSH

The increasing resistance of pathogens to common antibiotics, as well as the need to control urease activity to improve the yield of soil nitrogen fertilization in agricultural applications, has stimulated the development of novel classes of molecules that target urease as an enzyme. In this context, the newly developed compounds on the basis of 1-heptanoyl-3-arylthiourea family were evaluated for Jack bean urease enzyme inhibition activity to validate their role as potent inhibitors of this enzyme. 1-Heptanoyl-3-arylthioureas were obtained in excellent yield and characterized through spectral and elemental analysis. All the compounds displayed remarkable potency against urease inhibition as compared to thiourea standard. It was found that novel compounds fulfill the criteria of drug-likeness by obeying Lipinski's rule of five. Particularly compound 4a and 4c can serve as lead molecules in 4D (drug designing discovery and development). Kinetic mechanism and molecular docking studies also carried out to delineate the mode of inhibition and binding affinity of the molecules.

• Klíčová slova
• Acyl thioureas, Antioxidant, Jack bean urease, Kinetic mechanism, Lipinski’s rules, Molecular modeling, Urease,
• MeSH
• Canavalia enzymologie   MeSH
• inhibitory enzymů chemie   farmakologie   MeSH
• kinetika MeSH
• molekulární struktura MeSH
• simulace molekulového dockingu * MeSH
• thiomočovina chemie   farmakologie   MeSH
• ureasa antagonisté a inhibitory   metabolismus   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• inhibitory enzymů MeSH
• thiomočovina MeSH
• ureasa MeSH

Stomach infection with Helicobacter pylori (H. pylori) causes severe gastroduodenal diseases in a large number of patients worldwide. The H. pylori infection breaks up in early childhood, persists lifelong if not treated, and is associated with chronic gastritis and an increased risk of peptic ulcers and gastric cancer. In recent years, the problem of drug-resistant strains has become a global concern that makes the treatment more complicated and the infection persistent at higher levels when the antibiotic treatment is stopped. Such problems have led to the development of new strategies to eradicate an H. pylori infection. Currently, one of the most important strategies for the treatment of H. pylori infection is the use of urease inhibitors. Despite the fact that large numbers of molecules have been shown to exert potent inhibitory activity against H. pylori urease, most of them were prevented from being used in vivo and in clinical trials due to their hydrolytic instability, toxicity, and appearance of undesirable side effects. Therefore, it is crucial to focus attention on the available opportunities for the development of urease inhibitors with suitable pharmacokinetics, high hydrolytic stability, and free toxicological profiles. In this commentary, we aim to afford an outline on the current status of the use of urease inhibitors in the treatment of an H. pylori infection, and to discuss the possibility of their development as effective drugs in clinical trials.

• Klíčová slova
• Helicobacter pylori (H. pylori) infection, children, drug development, pharmacokinetics, urease inhibitors,
• Publikační typ
• časopisecké články MeSH

Furan chalcone scaffolds belong to the most privileged and promising oxygen-containing heterocyclic class of compounds, which have a wide spectrum of therapeutic applications in the field of pharmaceutics, pharmacology, and medicinal chemistry. This research described the synthesis of a series of twelve novel and seven reported furan chalcone (conventional synthetic approach) analogues 4a-s through the application of microwave-assisted synthetic methodology and evaluated for therapeutic inhibition potential against bacterial urease enzyme. In the first step, a series of nineteen substituted 5-aryl-2-furan-2-carbaldehyde derivatives 3a-s were achieved in moderate to good yields (40-70%). These substituted 5-aryl-2-furan-2-carbaldehyde derivatives 3a-s were condensed with acetophenone via Claisen-Schmidt condensation to furnish 19 substituted furan chalcone scaffolds 4a-s in excellent yields (85-92%) in microwave-assisted synthetic approach, while in conventional methodology, these furan chalcone 4a-s were furnished in good yield (65-90%). Furan chalcone structural motifs 4a-s were characterized through elemental analysis and spectroscopic techniques. These nineteen (19)-afforded furan chalcones 4a-s were screened for urease inhibitory chemotherapeutic efficacy and most of the furan chalcones displayed promising urease inhibition activity. The most active urease inhibitors were 1-phenyl-3-[5-(2',5'-dichlorophenyl)-2-furyl]-2-propen-1-one 4h with an IC50 value of 16.13 ± 2.45 μM, and 1-phenyl- 3-[5-(2'-chlorophenyl)-2-furyl] -2-propen-1-one 4s with an IC50 value of 18.75 ± 0.85 μM in comparison with reference drug thiourea (IC50 = 21.25 ± 0.15 μM). These furan chalcone derivatives 4h and 4s are more efficient urease inhibitors than reference drug thiourea. Structure-activity relationship (SAR) revealed that the 2,5-dichloro 4h and 2-chloro 4s moiety containing furan chalcone derivatives may be considered as potential lead reagents for urease inhibition. The in silico molecular docking study results are in agreement with the experimental biological findings. The results of this study may be helpful in the future drug discovery and designing of novel efficient urease inhibitory agents from this biologically active class of furan chalcones.

• Klíčová slova
• Claisen–Schmidt condensation, SAR, furan carbaldehyde, furan chalcones, molecular docking, urease inhibition,
• Publikační typ
• časopisecké články MeSH

UNLABELLED: In this review, an overview of the available literature on urease is presented. Urease is an enzyme which catalyzes the hydrolysis of urea. The occurrence of ureases and their functions are discussed thoroughly. The relationship of urease to ureolytic bacteria is examined, and the currently available urease inhibitors, both inorganic and natural, are presented. Finally, the importance of urease and current and future applications of new inhibitors and explored. KEYWORDS: bacteria inhibitor urease.

• Publikační typ
• časopisecké články MeSH

Studies on enzyme inhibition remain a crucial area in drug discovery since these studies have led to the discoveries of new lead compounds useful in the treatment of several diseases. In this study, protocatechuic acid (PCA), an active compound from Hibiscus sabdariffa L. has been evaluated for its inhibitory properties against jack bean urease (JBU) as well as its possible toxic effect on human gastric epithelial cells (GES-1). Anti-urease activity was evaluated by an Electrospray Ionization-Mass Spectrometry (ESI-MS) based method, while cytotoxicity was assayed by the MTT method. PCA exerted notable anti-JBU activity compared with that of acetohydroxamic acid (AHA), with IC50 values of 1.7 and 3.2 µM, respectively. PCA did not show any significant cytotoxic effect on (GES-1) cells at concentrations ranging from 1.12 to 3.12 µM. Molecular docking study revealed high spontaneous binding ability of PCA to the active site of urease. Additionally, the anti-urease activity was found to be related to the presence of hydroxyl moieties of PCA. This study presents PCA as a natural urease inhibitor, which could be used safely in the treatment of diseases caused by urease-producing bacteria.

• Klíčová slova
• ESI-Mass spectrometry, Hibiscus sabdariffa L., cytotoxicity, molecular docking, protocatechuic acid, urease inhibitors,
• MeSH
• buněčné linie MeSH
• Hibiscus chemie   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
• hydroxybenzoáty chemie   MeSH
• kyseliny hydroxamové chemie   MeSH
• lidé MeSH
• simulace molekulového dockingu metody   MeSH
• ureasa antagonisté a inhibitory   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• acetohydroxamic acid MeSH Prohlížeč
• hydroxybenzoáty MeSH
• kyseliny hydroxamové MeSH
• protocatechuic acid MeSH Prohlížeč
• ureasa MeSH

AIMS: The aim of the present research was to synthesize glycoluril derivative 2,4-Bis(4- cyanobenzyl)glycoluril through a convergent scheme. BACKGROUND: For this purpose, Sandmeyer reaction procedure was employed for the synthesis of said compound. The structure of the pure compound was confirmed by using different spectroscopic techniques, such as 1HNMR, 13C-NMR and (HR-MS) Mass spectrometry. OBJECTIVE: Convergent synthesis of 2,4-BIS (4-CYANOBENZYL)GLYCOLURIL USING SANDMEYER REACTION and urease inhibition study. METHODS: The structure of the pure compound was confirmed by using different spectroscopic techniques such as 1H-NMR, 13C-NMR and (HR-MS) Mass spectrometry. The electronic properties of the newly synthesized compound and thiourea were determined by using density functional theory. RESULTS: Furthermore, the compound was evaluated against urease enzyme and was found to be potent inhibitors with an IC50 value of 11.5 ± 1.50 μM when compared with standard inhibitor thiourea (IC50 = 21.0 ± 1.90 μM). The compound may serve as a lead compound to synthesize new cyano-based bambusuril in the future with enhanced biological properties. CONCLUSION: We have synthesized a new glycoluril derivative 2,4-Bis(4-cyanobenzyl)glycoluril by the sandmeyer reaction. It has been obtained in the form of light yellowish powder in good yield (96%). Glycoluril based macrocycles have been used in various fields; starting from the 2,4-Bis(4-nitrobenzyl)glycoluril (already reported compound), which has undergone reduction (CH3OH,Pt/C) , diazotization (NaNO2/HCl), cyanation (CuCl/KCN), respectively in order to synthesize the desired new glycoluril derivative. The obtained product will be used as a building block for the synthesis of the cyano based bambusuril marcocycle in the future. The yield of the obtained product has been monitored by using different amounts of cyanating reagent, but the best results are shown by the use of 4 mmol of CuCl/KCN. KCN with CuCl assisted the conversion of diazo group into the cyano group with enhanced yield when used in excess amount. It acts as a catalyst. The solubility characteristic of 2,4-Bis(4-cyanobenzyl)glycoluril has also been determined in different organic solvents. 1H NMR technique proved to be very helpful for the structure determination of our desired product. Benzylic protons give signals at 7.5 ppm and 7.8 ppm, respectively. The downfield peaks confirm the presence of CN group near the benzylic protons. Methine protons show a signal at 5.2 ppm, which ensures the basic skeleton of glycoluril. Ureidyl protons also confirm the synthesis of the heterocyclic 2,4-Bis(4-cyanobenzyl)glycoluril compound. The negative and positive electrostatic potential sites, molecular descriptors, and charge density distribution of frontier molecular orbitals are revealing that 4a with promising sites for electrophilic and nucleophilic attacks would result to enhance the urease inhibition, which is in good agreement with the experimental data.

• Klíčová slova
• (HR-MS) mass spectrometry, 1H NMR, Glycoluril derivative, IC50, bambusuril., density functional theory (DFT), sandmeyer reaction, thiourea, urease enzyme,
• MeSH
• heterocyklické sloučeniny bicyklické MeSH
• imidazolidiny MeSH
• imidazoly MeSH
• inhibitory enzymů * farmakologie   MeSH
• simulace molekulového dockingu MeSH
• teorie funkcionálu hustoty MeSH
• ureasa * metabolismus   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• glycoluril MeSH Prohlížeč
• heterocyklické sloučeniny bicyklické MeSH
• imidazolidiny MeSH
• imidazoly MeSH
• inhibitory enzymů * MeSH
• ureasa * MeSH

Proteus mirabilis is a major bacterium responsible for catheter-associated urinary tract infections (CAUTIs). Urease enzyme has a great role in the pathogenesis of Proteus mirabilis. Using urease, Proteus mirabilis can decompose urea to produce ammonia that increases urine pH and enhances crystal precipitation and crystalline biofilm formation. This leads to catheter blockage and pyelonephritis, respectively. Urease inhibitors are of great value in controlling this problem. Diclofenac sodium and ketorolac tromethamine, with their metal chelating activities, can inactivate urease by chelation of nickel ion in the active site of urease. This study investigated the ability of diclofenac sodium and ketorolac tromethamine to inhibit urease activity in Proteus mirabilis and crystalline biofilm formation. Diclofenac sodium and ketorolac tromethamine showed comparable activities against urease in cell lysates and whole cultures, with subsequent inhibition of pH increase and crystal formation in artificial urine. Diclofenac sodium showed higher biofilm inhibition and downregulation of urease genes ureR and ureC in RT-qPCR. The docking study showed the ability of both drugs to bind to urease enzyme and to chelate nickel ions in the active site of urease, suggesting that nickel chelation is the mode of inhibition of urease enzyme. In conclusion, diclofenac sodium and ketorolac tromethamine are two urease inhibitors that may be useful in treating Proteus mirabilis CAUTI.

• Klíčová slova
• Proteus mirabilis, CAUTI, Chelation, Diclofenac sodium, Ketorolac tromethamine, Urease inhibition,
• Publikační typ
• časopisecké články MeSH

For decades, Hibiscus sabdariffa L. and its phytochemicals have been shown to possess a wide range of pharmacologic properties. In this study, aqueous extract of Hibiscus sabdariffa (AEHS) and its bioactive constituent protocatechuic acid (PCA), have been evaluated in vitro for their antiviral activity against HSV-2 clinical isolates and anti-enzymatic activity against urease. Antiherpetic activity was evaluated by the titer reduction assay in infected Vero cells, and cytotoxicity was evaluated by the neutral red dye-uptake method. Anti-urease activity was determined by a developed Electrospray Ionization-Mass Spectrometry (ESI-MS)-based assay. PCA showed potent anti-HSV-2 activity compared with that of acyclovir, with EC50 values of 0.92 and 1.43 µg∙mL-1, respectively, and selectivity indices > 217 and > 140, respectively. For the first time, AEHS was shown to exert anti-urease inhibition activity, with an IC50 value of 82.4 µg∙mL-1. This, combined with its safety, could facilitate its use in practical applications as a natural urease inhibitor. Our results present Hibiscus sabdariffa L. and its bioactive compound PCA as potential therapeutic agents in the treatment of HSV-2 infection and the treatment of diseases caused by urease-producing bacteria.

• Klíčová slova
• ESI-mass spectrometry-based assay, Hibiscus sabdariffa L., anti-HSV-2 activity, bacterial infection, protocatechuic acid, urease inhibitors,
• MeSH
• acyklovir farmakologie   MeSH
• antivirové látky chemie   izolace a purifikace   farmakologie   MeSH
• Cercopithecus aethiops MeSH
• Hibiscus chemie   MeSH
• hmotnostní spektrometrie s elektrosprejovou ionizací MeSH
• inhibiční koncentrace 50 MeSH
• inhibitory enzymů chemie   izolace a purifikace   farmakologie   MeSH
• kinetika MeSH
• lidský herpesvirus 2 účinky léků   MeSH
• polyfenoly chemie   izolace a purifikace   farmakologie   MeSH
• preklinické hodnocení léčiv MeSH
• rostlinné extrakty chemie   izolace a purifikace   farmakologie   MeSH
• ureasa antagonisté a inhibitory   chemie   MeSH
• Vero buňky MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• acyklovir MeSH
• antivirové látky MeSH
• inhibitory enzymů MeSH
• polyfenoly MeSH
• rostlinné extrakty MeSH
• ureasa MeSH

In this study, we explored the role of biochar (BC) and/or urease inhibitor (UI) in mitigating ammonia (NH3) and nitrous oxide (N2O) discharge from urea fertilized wheat cultivated fields in Pakistan (34.01°N, 71.71°E). The experiment included five treatments [control, urea (150 kg N ha-1), BC (10 Mg ha-1), urea + BC and urea + BC + UI (1 L ton-1)], which were all repeated four times and were carried out in a randomized complete block design. Urea supplementation along with BC and BC + UI reduced soil NH3 emissions by 27% and 69%, respectively, compared to sole urea application. Nitrous oxide emissions from urea fertilized plots were also reduced by 24% and 53% applying BC and BC + UI, respectively, compared to urea alone. Application of BC with urea improved the grain yield, shoot biomass, and total N uptake of wheat by 13%, 24%, and 12%, respectively, compared to urea alone. Moreover, UI further promoted biomass and grain yield, and N assimilation in wheat by 38%, 22% and 27%, respectively, over sole urea application. In conclusion, application of BC and/or UI can mitigate NH3 and N2O emissions from urea fertilized soil, improve N use efficiency (NUE) and overall crop productivity.

• Publikační typ
• časopisecké články MeSH