Potent Urease Inhibitors Research Articles

Hydroxamic Acids Derivatives: Greener Synthesis, Antiureolytic Properties And Potential Medicinal Chemistry Applications - A Concise Review.

Hydroxamic acids (HAs) are chemical compounds characterized by the general structure RCONR'OH, where R and R' can denote hydrogen, aryl, or alkyl groups. Recognized for their exceptional chelating capabilities, HAs can form mono or bidentate complexes through oxygen and nitrogen atoms, rendering them remarkably versatile. These distinctive structural attributes have paved the way for a broad spectrum of medicinal applications for HAs, among which their pivotal role as inhibitors of essential Ni(II) and Zn(II)-containing metalloenzymes. In 1962, a significant breakthrough occurred when Kobashi and colleagues identified hydroxamic acids (HAs) as potent urease inhibitors. Subsequent research has increasingly underscored their capability in combatting infections induced by ureolytic microorganisms, including Helicobacter pylori and Proteus mirabilis. However, comprehensive reviews exploring their potential applications in treating infections caused by ureolytic microorganisms remain scarce in the scientific literature. Thus, this minireview aims to bridge this gap by offering a systematic exploration of the subject. Furthermore, it seeks to explore the significant advancements in obtaining hydroxamic acid derivatives through environmentally sustainable methodologies.

Synthesis, Urease Inhibition, Molecular Docking, and Optical Analysis of a Symmetrical Schiff Base and Its Selected Metal Complexes.

Designing and developing small organic molecules for use as urease inhibitors is challenging due to the need for ecosystem sustainability and the requirement to prevent health risks related to the human stomach and urinary tract. Moreover, imaging analysis is widely utilized for tracking infections in intracellular and in vivo systems, which requires drug molecules with emissive potential, specifically in the low-energy region. This study comprises the synthesis of a Schiff base ligand and its selected transition metals to evaluate their UV/fluorescence properties, inhibitory activity against urease, and molecular docking. Screening of the symmetrical cage-like ligand and its metal complexes with various eco-friendly transition metals revealed significant urease inhibition potential. The IC50 value of the ligand for urease inhibition was 21.80 ± 1.88 µM, comparable to that of thiourea. Notably, upon coordination with transition metals, the ligand-nickel and ligand-copper complexes exhibited even greater potency than the reference compound, with IC50 values of 11.8 ± 1.14 and 9.31 ± 1.31 µM, respectively. The ligand-cobalt complex exhibited an enzyme inhibitory potential comparable with thiourea, while the zinc and iron complexes demonstrated the least activity, which might be due to weaker interactions with the investigated protein. Meanwhile, all the metal complexes demonstrated a pronounced optical response, which could be utilized for fluorescence-guided targeted drug delivery applications in the future. Molecular docking analysis and IC50 values from in vitro urease inhibition screening showed a trend of increasing activity from compounds 7d to 7c to 7b. Enzyme kinetics studies using the Lineweaver-Burk plot indicated mixed-type inhibition against 7c and non-competitive inhibition against 7d.

Novel benzimidazole-based azine derivatives as potent urease inhibitors: synthesis, in vitro and in silico approach

Novel benzimidazole-based azine derivatives as potent urease inhibitors: synthesis, <i>in vitro</i> and <i>in silico</i> approach

Benzimidazole-acrylonitrile hybrid derivatives act as potent urease inhibitors with possible fungicidal activity

Benzimidazole-acrylonitrile hybrid derivatives act as potent urease inhibitors with possible fungicidal activity

Synthesis and anti-ureolitic activity of Biginelli adducts derived from formylphenyl boronic acids

Urease is a metalloenzyme that contains two Ni(II) ions in its active site and catalyzes the hydrolysis of urea into ammonia and carbon dioxide. The development of effective urease inhibitors is crucial not only for mitigating nitrogen losses in agriculture but also for offering an alternative treatment against infections caused by resistant pathogens that utilize urease as a virulence factor. This study focuses on synthesizing and investigating the urease inhibition potential of Biginelli Adducts bearing a boric acid group. An unsubstituted or hydroxy-substituted boronic group in the Biginelli adducts structure enhances the urease inhibitory activity. Biophysical and kinetics studies revealed that the best Biginelli adduct (4e; IC50 = 132 ± 12 µmol/L) is a mixed inhibitor with higher affinity to the urease active site over an allosteric one. Docking studies confirm the interactions of 4e with residues essential for urease activity and demonstrate its potential to coordinate with the nickel atoms through the oxygen atoms of carbonyl or boronic acid groups. Overall, the Biginelli adduct 4e shows great potential as an additive for developing enhanced efficiency fertilizers and/or for medical applications.

Synthesis of 1,2,3-triazole functionalized derivatives of metronidazole as potent inhibitors of urease: Synthesis via click chemistry, in vitro urease inhibition, kinetics and molecular docking studies

Current study is based on multistep synthesis of sixteen new 1,2,3-triazole functionalized derivatives of metronidazole drug 3–18 by using a Cu(I)-catalysed 1,3-dipolar azide-alkyne cycloaddition (CuAAC) reaction via a click chemistry approach. All the compounds were purified by using conventional silica gel column chromatography with isocratic eluent. Their structures were confirmed by using various spectroscopic techniques including UV, IR, LR and HR MS, 1H-, 13CNMR , and 2D-NMR spectroscopy. The library of 1,2,3-triazole derivatives of metronidazole 3–18 was evaluated for urease inhibitory activity, and cytotoxicity against normal cells. Compound 8 (IC50= 6.8 ± 0.8 µM) was found to be the most potent urease inhibitor, while acetohydroxamic acid (IC50 = 20.3 ± 0.4 µM) was used as experimental standard. Compounds 5 (IC50 = 7.9 ± 0.9 µM), 6 (IC50 = 9.5 ± 0.2 µM), 7 (IC50 = 8.5 ± 1.0 µM), 10 (IC50 = 9.3 ± 1.1 µM), and 18 (IC50 = 7.2 ± 0.6 µM) were also found to be potent inhibitors of urease. Parent drug metronidazole also showed a potent urease enzyme inhibitory activity with IC50= 10.54 ± 0.8 µM. All compounds were found to be non-cytotoxic against the human fibroblast (B.J.) cell line. Molecular docking and kinetic studies were performed for compounds 5–8, 10, and 18 which showed that these compounds are competitive inhibitors of urease enzyme inhibition. Urease inhibition is a therapeutic approach to help in the treatment of peptic ulcers, caused by ureolytic bacteria. The initial findings presented herein therefore, deserve further studies.

Designing and Synthesis of Novel Fexofenadine-Derived Hydrazone-Schiff Bases as Potential Urease Inhibitors: In-Vitro, Molecular Docking and DFT Investigations.

Thirteen novel hydrazone-Schiff bases (3-15) of fexofenadine were succesfully synthesized, structurally deduced and finally assessed their capability to inhibit urease enzyme (in vitro). In the series, six compounds 12 (IC50=10.19±0.16 μM), 11 (IC50=15.05±1.11 μM), 10 (IC50=17.01±1.23 μM), 9 (IC50=17.22±0.81 μM), 13 (IC50=19.31±0.18 μM), and 14 (IC50=19.62±0.21 μM) displayed strong inhibitory action better than the standard thiourea (IC50=21.14±0.24 μM), while the remaining compounds displayed significant to less inhibition. LUMO and HOMO showed the transferring of charges from molecules to biological transfer and MEP map showed the chemically reactive zone appropriate for drug action are calculated using DFT. AIM charges, non-bonding orbitals, and ELF are also computed. The urease protein binding analysis benefited from the docking studies.

Design and discovery of urease and Helicobacter pylori inhibitors based on benzofuran/benzothiophene-sulfonate and sulfamate scaffolds for the treatment of ureolytic bacterial infections

A series of sulfonate and sulfamate derivatives bearing benzofuran or benzothiophene scaffold exhibited potent inhibitory effect on urease enzyme. Most of the derivatives exhibited significantly higher potency than thiourea, the standard inhibitor. Compound 1s was identified as the most potent urease inhibitor with an IC50 value of 0.42 ± 0.08 μM, which is 53-fold more potent than thiourea, positive control (IC50 = 22.3 ± 0.031 μM). The docking results further revealed the binding interactions towards the urease active site. Phenotypic screening revealed that compounds 1c, 1d, 1e, 1f, 1j, 1n, and 1t exhibit high potency against H. pylori with MIC values ranging from 0.00625 to 0.05 mM and IC50 values ranging from 0.0031 to 0.0095 mM, much more potent than the positive control, acetohydroxamic acid (MIC and IC50 values were 12.5 and 7.38 mM, respectively). Additional studies were performed to investigate the toxicity of these compounds against the gastric epithelial cell line (AGS) and their selectivity profile against E. coli, and five Lactobacillus species representative of the gut microflora. Permeability characteristics of the most promising derivatives were investigated in Caco-2 cell line. The results indicate that the compounds could be targeted in the GIT only without systemic side effects.

Synthesis of novel 2-mercapto-1,3,4-oxadiazole derivatives as potent urease inhibitors: In vitro and in silico investigations

In the present work seven derivatives (5a-5d and 6a-6c) of 2-mercapto-1,3,4-oxadiazole were synthesized by multistep reactions. After characterization through IR, EI-MS, 1H-, and 13C NMR spectroscopy, the synthesized compounds were screened in vitro against urease enzyme. Among the series, five derivatives 6c (IC50 = 9.90 ± 1.92 µM), 6a (IC50 = 10.65 ± 1.80 µM), 6b (IC50 = 12.30 ± 0.99 µM), 5c (IC50 = 12.57 ± 0.41 µM), and 5d (IC50 = 16.96 ± 0.64 µM) attributed excellent inhibition effect excellent than the standard thiourea (IC50 = 22.80 ± 2.20 µM). In addition, the remaining four compounds 5a, 5b, 4, and 3 were found good inhibitors against the urease enzyme with IC50 values of 23.23 ± 0.17, 25.20 ± 0.90, 31.40 ± 1.18, and 36.77 ± 1.03 µM respectively. The cytotoxicity assay revealed that the synthetic derivatives did not show any cytotoxic effect. DFT used to calculate frontier molecular orbital including; HOMO and LUMO to indicate the charge transfer from molecule to biological media, and MEP map to indicate the chemically reactive zone suitable for drug action. The results of docking and MD simulation indicate that most active mercapto-1,3,4-oxadiazoles have high binding efficiency to urease. The In silico ADMET indicated that 5a-d and 6a-c compounds did not exhibit carcinogenicity, mutagenicity or tumorigenicity.

Chemical Constituents and Bioactivities of Nepeta Taxa Essential Oils from Turkey: Principal Component Analysis, Molecular Docking Study, Molecular Dynamics, MM‐PBSA and Drug‐Likeness Estimation

AbstractNepeta taxa are popular plants and sources of traditional Turkish medicine. Chemical constituents in the essential oils (EOs) hydrodistilled from above‐ground parts of Nepeta aristata (NA), N. baytopii (NB), N. italica (NI), N. nuda (NN), and N. stenantha (NS) were determined using GC‐MS. The pharmacological activities of EOs, such as biological activities, were evaluated in vitro. DNA protection activities of NS‐EO were found to be the most effective. The NA‐EO, NI‐EO, and NS‐EO were more potent urease inhibitors, while the NS‐EO exhibited potent AChE inhibitors. Their molecular docking, molecular dynamics and enzyme inhibition results were compatible with the major components. Furthermore, MolDock and binding affinity results were found to be high. Moreover, AChE‐tau‐cadinol, BChE‐tau‐cadinol and tyrosinase‐Caryophyllene oxide complexes showed stability when simulated for 100 ns, with high MM‐PBSA energy values. In addition, the main components′ pharmacokinetic properties were observed to be effective. The present study showed that EOs may be valuable natural products for future pharmacological research, food, and the cosmetic industry according to in vitro and in silico values.

New thiosemicarbazone analogues: synthesis, urease inhibition, kinetics and molecular docking studies

The current research reports the synthesis of a library of thiosemicarbazones (3-16) through a two-step chemical transformation. All the synthesized derivatives were purified and fully characterized through mass spectrometry, NMR spectroscopy (1H-, and 13C-NMR), and IR spectroscopy. All the members of the synthesized library were found to be new except compound 8. The synthesized library was screened for its inhibition potential against the urease enzyme. Almost all the compounds exhibited potent activity with the IC50 = 5.3 ± 0.8 − 15.5 ± 0.6 µM in comparison to the thiourea and acetohydroxamic acid used as standard (IC50 = 21.1 ± 0.2, 20.5 ± 0.4 µM). While significant activity was exhibited by compounds 14 and 15 with the IC50 = 23.6 ± 0.6 and 27.3 ± 1.2 µM. Furthermore, kinetic studies were carried out to determine the inhibition mode and molecular docking was employed to recognize the ligand-enzyme interactions. Thereby, the docking results are well in the direction of the in vitro results. Compounds ((E)-N-(2,5-dichlorophenyl)-2-(4-fluorobenzylidene)hydrazine-1-carbothioamide (3) and (E)-2-(2-chlorobenzylidene)-N-(2-fluorophenyl) hydrazinecarbothioamide (5) were identified as the most potent inhibitors of urease by both the in vitro and in silico studies.

Machine Learning-Driven Classification of Urease Inhibitors Leveraging Physicochemical Properties as Effective Filter Criteria.

Urease, a pivotal enzyme in nitrogen metabolism, plays a crucial role in various microorganisms, including the pathogenic Helicobacter pylori. Inhibiting urease activity offers a promising approach to combating infections and associated ailments, such as chronic kidney diseases and gastric cancer. However, identifying potent urease inhibitors remains challenging due to resistance issues that hinder traditional approaches. Recently, machine learning (ML)-based models have demonstrated the ability to predict the bioactivity of molecules rapidly and effectively. In this study, we present ML models designed to predict urease inhibitors by leveraging essential physicochemical properties. The methodological approach involved constructing a dataset of urease inhibitors through an extensive literature search. Subsequently, these inhibitors were characterized based on physicochemical properties calculations. An exploratory data analysis was then conducted to identify and analyze critical features. Ultimately, 252 classification models were trained, utilizing a combination of seven ML algorithms, three attribute selection methods, and six different strategies for categorizing inhibitory activity. The investigation unveiled discernible trends distinguishing urease inhibitors from non-inhibitors. This differentiation enabled the identification of essential features that are crucial for precise classification. Through a comprehensive comparison of ML algorithms, tree-based methods like random forest, decision tree, and XGBoost exhibited superior performance. Additionally, incorporating the "chemical family type" attribute significantly enhanced model accuracy. Strategies involving a gray-zone categorization demonstrated marked improvements in predictive precision. This research underscores the transformative potential of ML in predicting urease inhibitors. The meticulous methodology outlined herein offers actionable insights for developing robust predictive models within biochemical systems.

Fluoroquinolone and enoxacin molecules are potential urease inhibitors for treating ureolytic bacterial infections

Urease, a nickel-dependent metalloenzyme, has emerged as a significant therapeutic target due to its role in promoting the pathogenesis of various human health conditions. These include the development of pyelonephritis, urolithiasis, peptic ulcers, hepatic encephalopathy, and gastric ulcers. The currently available treatment involved the usage of strong antibiotics along with proton pump inhibitors to cope with the infection of urease producing bacteria. These conventional treatments are becoming less effective as bacteria are gaining multiple drug resistance. Therefore, there is a crucial need to identify alternative compounds with potential anti-urease activity and minimal side effects. Fluoroquinolones and Enoxacin derivatives offer antimicrobial, anti-inflammatory, antioxidant, anti-diabetic, and anti-urease activities. To improve the chemical diversity of urease inhibitors, different series of fluoroquinolones and Enoxacin derivatives were evaluated against urease and their antioxidant activity was also evaluated. To achieve this objective, in-silico studies were conducted utilizing molecular docking and adsorption, distribution, metabolism, excretion, and toxicology (ADMET) models. These analyses were employed to explore potential binding mechanisms and assess the drug-likeness of the compounds against urease enzymes. The inhibitory effect of docked heterocyclic compounds was also verified in-vitro against urease enzyme. Fluoroquinolones derivatives were found to be active inhibitors at high dose levels but showed minimum inhibition at low concentration. The compound EN from the Enoxacin series exhibited the highest potency as a urease inhibitor, with an IC50 of 45.86 μM, out-performing the standard drug thiourea, which had an IC50 of 52.20 μM. Additionally, compounds NOX-3 and FB-17 from the fluoroquinolone and Enoxacin series demonstrated significant DPPH free radical scavenging activity, with IC50 values of 98.17 μM and 97.98 μM, respectively. These results were comparable to the positive control ascorbic acid, which had an IC50 of 48.15 μM. This study demonstrates that Enoxacin derivatives can be further analyzed as potent urease inhibitors, while both Enoxacin and fluoroquinolone derivatives can be developed into more effective drugs to overcome oxidative stress.

Antioxidant and enzyme inhibitory potentials of phytochemicals isolated from Dioclea reflexa (Hook F.) stem: in-vitro and in-silico studies

The objective of the study was to isolate and characterize phytochemicals from the stem extract of D. reflexa and investigate their biochemical activities. Five flavonoids together with two terpenoids, were isolated. Their structures were identified using 1D and 2D nuclear magnetic resonance (NMR) and mass spectroscopic techniques in combination with circular dichroism (CD) spectroscopy, as well as comparisons with published data. The in vitro reactive oxygen species scavenging potential of the compounds was investigated. The lipoxygenase and urease inhibitory potential of the compounds were tested using in vitro and in silico methods. Compound 1 and 2 exhibited potent antioxidant activity with lower IC50 values of 38.5 ± 0.25 and 39.5± 0.14 μM respectively compared with the standard used (BHA IC50 value = 39.5± 0.14) in DPPH assay. Compound 1 and 2 also exhibit good reducing ability and superoxide radical scavenging activity reflected by IC50 value 44.6 ± 0.30 and 48.5 ± 0.16 respectively compared with BHA (IC50 45.6 ± 0.54). Compound 2 and 3 showed significant inhibitory effect against urease with IC50 values 26.2 ± 0.29 μM and 36.5 ± 0.37 μM respectively, while compound 4 with IC50 value 33.3 ± 0.74 μM is the most active against lipoxygenase. All the seven compounds showed varying degrees of binding affinity against the targets with compounds 1–5 having the better docking score compared with the co-crystalized ligands of both lipoxygenase and urease. The density functional theory reveals the replicate of the transitional state between the compounds and their respective receptor and stability of the compounds was predicted from the energy gap (ELUMO – EHOMO). These compounds are potential drug against stomach ulcers, inflammation and oxidative stress associated diseases. It is also worth mentioning that the complete assignments of NMR data 1 and 2 were reported for the first time in this study.

Synergizing structure and function: Cinnamoyl hydroxamic acids as potent urease inhibitors

The current investigation encompasses the structural planning, synthesis, and evaluation of the urease inhibitory activity of a series of molecular hybrids of hydroxamic acids and Michael acceptors, delineated from the structure of cinnamic acids. The synthesized compounds exhibited potent urease inhibitory effects, with IC50 values ranging from 3.8 to 12.8 µM. Kinetic experiments unveiled that the majority of the synthesized hybrids display characteristics of mixed inhibitors. Generally, derivatives containing electron-withdrawing groups on the aromatic ring demonstrate heightened activity, indicating that the increased electrophilicity of the beta carbon in the Michael Acceptor moiety positively influences the antiureolytic properties of this compounds class. Biophysical and theoretical investigations further corroborated the findings obtained from kinetic assays. These studies suggest that the hydroxamic acid core interacts with the urease active site, while the Michael acceptor moiety binds to one or more allosteric sites adjacent to the active site.

D-Glucosamine is a Potential Urease Inhibitor from Middle Eastern Medicinal Plants for Combatting Helicobacter Pylori Infections; a Molecular Docking and Simulation Approach.

Helicobacter pylori stands as a significant risk factor for both peptic and stomach ulcers. Their resistance to the highly acidic host environment primarily stems from their capability to produce urease, an enzyme that rapidly converts urea into NH3 and CO2. These byproducts are crucial for the bacterium's survival under such harsh conditions. Given the pivotal role of medicinal plants in treating various ailments with minimal side effects, there is an urgent need for a natural drug that can effectively eliminate H. pylori by inhibiting urease. Hence, the current study aims to identify the most potent urease inhibitor among the natural compounds found in Middle Eastern medicinal plants, taking into consideration factors such as optimal affinity, drug-like properties, pharmacokinetic characteristics, and thermodynamic attributes. In total, 5599 ligand conformers from 151 medicinal plants were subjected to docking against the urease's active site. The top-ranking natural compounds, as determined by their high docking scores, were selected for further analysis. Among these compounds, D-glucosamine (PubChem code 439,213) exhibited the most interactions with the crucial amino acid residues in the urease's active site. Furthermore, D-glucosamine demonstrated superior absorption, distribution, metabolism, excretion, and toxicity properties compared to other top-ranked candidates. Molecular dynamics simulations conducted over 100 nanoseconds revealed stable root mean square deviations and fluctuations of the protein upon complexation with D-glucosamine. Additionally, the radius of gyration and solvent-accessible surface area values for the D-glucosamine-urease complex were notably lower than those observed in other typical urease-inhibitor complexes. In conclusion, this study provides valuable insights into the potential development of D-glucosamine as a novel urease inhibitor. This promising compound holds the potential to serve as an effective drug for combating H. pylori infections in the near future.

Identification of potential drug candidates to treat gastritis and associated oxidative stress based on some novel 2-aryl-1H-naphtho[2,3-d]imidazole: synthesis, in vitro and in silico analysis.

To identify potential scaffolds to treat gastritis and oxidative stress, 2-aryl-1H-naphtho[2,3-d]imidazole derivatives (1-15) were synthesized. The synthesis was conveniently carried out by condensing 2,3-diaminonaphthalene with variously substituted aldehydes to yield 15 new 2-aryl-1H-naphtho[2,3-d]imidazole derivatives. Structures of all synthesized compounds were elucidated using MS and NMR spectroscopic techniques. Compounds containing an imidazole moiety have continued to spark interest in the field of medicinal chemistry due to their unique properties. In continuation of this statement, to further explore the biological potential of these types of compounds, newly synthesized imidazole derivatives were evaluated for their inhibitory potential against urease and antioxidant activities. Compounds 4 and 11 were identified as the most potent urease inhibitors in the series, with IC50 values of 34.2 ± 0.72 and 42.43 ± 0.65 μM, respectively. Compounds 1, 3, 6, 11, and 15, with EC50 values in the range of 37-75 μg ml-1, showed significant antioxidant activity. Molecular docking studies of the selected synthesized compounds 3, 4, 9, and 11 were also performed to determine their binding interaction with the jack bean urease. Through docking studies, it was revealed that all the compounds that showed good inhibitory potential against urease fit well within the protein's binding pocket. Furthermore, ADME analysis was carried out to explore the drug-likeness properties of the compounds. The findings of the present work revealed that compounds 4 and 11 could be better options to treat gastritis and associated oxidative stress.

Novel pyrazoline linked acyl thiourea pharmacophores as antimicrobial, urease, amylase and α-glucosidase inhibitors: design, synthesis, SAR and molecular docking studies.

In the present work, a small library of novel pyrazolinyl-acyl thiourea (5a-j) was designed and synthesized through a multistep sequence and the synthesized compounds were screened for their antifungal, antibacterial and antioxidant activities as well as urease, amylase and α-glucosidase inhibitory activities. The synthesized series (5a-o) was characterized using a combination of spectroscopic techniques, including FT-IR, 1H NMR and 13C NMR. All compounds (5a-j) were found to have significant potency against urease, α-glucosidase, α-amylase, and DPPH. The synthesized compounds were also screened for potential antibacterial and anti-fungal inhibition activities. IC50 values for all the prepared compounds for urease, α-glucosidase, amylase, and DPPH inhibition were determined and derivatives 5b and 5g were found to be the most potent urease inhibitors with IC50 values of 54.2 ± 0.32 and 43.6 ± 0.25 μM, respectively. Whilst compound 5b (IC50 = 68.3 ± 0.11 μM) is a potent α-glucosidase inhibitor, compound 5f (90.3 ± 1.08 μM) is a potent amylase inhibitor and compound 5b (103.4 ± 1.15 μM) is a potent antioxidant. The different substitutions on the phenyl ring were the basis for structure-activity relationship (SAR) study. The molecular docking study was performed for the confirmation of binding interactions.

Rational design and in vitro testing of new urease inhibitors to prevent urinary catheter blockage.

Catheter associated urinary tract infections (CAUTI) caused by urease-positive organisms can lead to catheter blockage: urease metabolizes urea in urine to ammonia causing an increase in pH and hence precipitation of struvite and apatite salts into the catheter lumen and bladder leading to blockage. Acetohydroxamic acid (AHA) is the only urease inhibitor currently approved for patient use, however, it is rarely used owing to its side effects. Here, we report the identification and development of new urease inhibitors discovered using a rational in silico drug design approach. A series of compounds were designed, the compounds were screened and filtered to identify three compounds which were tested in in vitro urease activity assays. N,N'-Bis(3-pyridinylmethyl)thiourea (Bis-TU) outperformed AHA in activity assays and was tested in an in vitro bladder model, where it significantly extended the lifetime of the catheter compared to AHA. Bis-TU was delivered via a diffusible balloon catheter directly to the site of activity, thus demonstrating localized drug delivery. This cost-effective drug design approach allowed the identification of a potent urease inhibitor, which could be improved through iterative repeats of the method, and the process of design could be utilized to target other diseases.

Urease inhibitory potential of pyridine-containing triazolothiadiazole and triazolothiadiazine scaffolds for the treatment of ulceration and kidney stone: in vitro screening, kinetics mechanism, and in silico computational analysis

The hyperactivity of urease enzyme leads to various complications including gastritis and peptic ulcer. A diverse variety of natural and synthetic inhibitors have shown a tremendous potential to inhibit the urease enzyme, thus decreasing the hyperactivity and reducing the risk for the development of urinary calculi and other similar problems. Therefore, we herein report a family of fused heterocycles such as triazolothiadiazoles (4a–h, 5a–f) and triazolothiadiazines (6a–h) as potential antiurease agents with IC50 values in the range 10.41–41.20 µM. Several compounds were identified as potential lead candidates. Among them, compounds 4e and 4f from triazolothiadiazole series showed the highest inhibitory potential with IC50 values of 11.62 ± 0.34 and 10.35 ± 0.14 µM), respectively, whereas 6e from triazolothiadiazine series emerged as the most potent inhibitor with an IC50 value of 10.41 ± 0.13 µM. These compounds exhibited two-fold strong inhibitory efficacy against urease as compared to standard inhibitor, thiourea (IC50 = 22.48 ± 0.67 µM). The mechanistic insights from kinetics experiments for compounds 4e, 4f, and 6e revealed the competitive mode of inhibition with Ki values of 8.65 ± 0.004, 7.04 ± 0.012, and 8.31 ± 0.007 µM, respectively. The in vitro results were further explored through in silico computational docking analysis which reflects that binding of ligands with Ni ions and His492 play a crucial role in urease inhibition. In silico predicted physicochemical properties and ADME profile reflect drug-like nature of these molecules. Communicated by Ramaswamy H. Sarma