Urea-Self Powered Biosensors: A Predictive Evolutionary Model for Human Energy Harvesting.

The objective of this study is to create a reliable predictive model for the electrochemical performance of self-powered biosensors that rely on urea-based biological energy sources. Specifically, this model focuses on the development of a human energy harvesting model based on the utilization of urea found in sweat, which will enable the development of self-powered biosensors. In the process, the potential of urea hydrolysis in the presence of a urease enzyme is employed as a bioreaction for self-powered biosensors. The enzymatic reaction yields a positive potential difference that can be harnessed to power biofuel cells (BFCs) and act as an energy source for biosensors. This process provides the energy required for self-powered biosensors as biofuel cells (BFCs). To this end, initially, the platinum electrodes are modified by multi-walled carbon nanotubes to increase their conductivity. After stabilizing the urease enzyme on the surface of the platinum electrode, the amount of electrical current produced in the process is measured. The optimal design of the experiments is performed based on the Taguchi method to investigate the effect of urea concentration, buffer concentration, and pH on the generated electrical current. A general equation is employed as a prediction model and its coefficients calculated using an evolutionary strategy. Also, the evaluation of effective parameters is performed based on error rates. The obtained results show that the established model predicts the electrical current in terms of urea concentration, buffer concentration, and pH with high accuracy.

Removal of cadmium and arsenic from water through biomineralization.

Due to anthropogenic activities, heavy metals such as cadmium (Cd) and arsenic (As) are one of the most toxic xenobiotics contaminating water, thus affecting human health and the environment. The objective of the present investigation was to study the effect of ureolytic bacteria Bacillus paramycoides-MSR1 for the bioremediation of Cd and As from contaminated water. The B. paramycoides showed high resistance to heavy metals, Cd and As, with minimum inhibitory concentration (MIC) of 12.84 µM and 48.54 µM, respectively. The urease activity and calcium carbonate (CaCO3) precipitation were evaluated in artificial wastewater with different concentrations of Cd (0, 10, 20, 30, 40, 50, and 60 µM) and As (0, 20, 40, 60, 80, and 100 µM). The maximum urease activity in Cd-contaminated artificial wastewater was observed after 96 hours, which showed a 76.1% decline in urease activity as the metal concentration increased from 0 to 60 µM. Similarly, 14.1% decline in urease activity was observed as the concentration of As was increased from 0 to 100 µM. The calcium carbonate precipitation at the minimum inhibitory concentration of Cd and As-contaminated artificial wastewater was 189 and 183 mg/100 ml, respectively. The percentage removal of metal from artificially contaminated wastewater with varied concentrations was analyzed using atomic absorption spectroscopy (AAS). After 168 hours of incubation, 93.13% removal of Cd and 94.25% removal of As were observed. Microstructural analysis proved the presence of calcium carbonate in the form of calcite, confirming removal of cadmium and arsenic by microbially induced calcium carbonate precipitation (MICCP) to be promising technique for water decontamination.

Investigating purification and activity analysis of urease enzyme extracted from jack bean source: A green chemistry approach.

Urease is an enzyme of historical importance in the field of biochemistry, generally microbial and plant urease is the primary sources of urease. The significant applications of urease enzyme are found to be foremost in food industry, medical equipment's and biosensors. In this work, urease has been extracted from Jack bean meal using ammonium sulphate and acetone precipitation. A significant amount of urease was precipitated and concentrated at 60% saturated solution of ammonium sulphate. The obtained precipitates were dissolved in 50 mM phosphate buffer (pH 8) after centrifugation, and subjected to sodium dodecyl-sulphate polyacrylamide gel electrophoresis (SDS-PAGE) to determine the molecular weight of urease. Results obtained from the SDS-PAGE were validated using Zymography. Anion exchange chromatography was used to separate the desired protein at different pH (7.0, 7.5 and 8.0). The eluted fractions were assessed for urease activity using phenol-nitroprusside dependent ammonia release assay. Under these assay conditions, one unit of urease activity was calibrated as the amount of enzyme liberating 1 µM of NH3 from urea per unit time. The eluted fraction and Zymography analysis show the purified urease observed at 90 kDa and activity of purified urease, respectively. The obtained results for specific activity (173.67Units mg) and % purification (99.71%) for urease has been compared with the available literature, which are found to be in close relation with existing results. The proposed method is a novel approach which has recorded highest % purification and specific activity. Furthermore, it can be suitable for extracting urease from jack bean source for various industrial applications.

Synthesis, Biological Evaluation and in Silico Studies of New Pyrazoline Derivatives Bearing Benzo[d]thiazol-2(3H)-one Moiety as Potential Urease Inhibitors.

Novel pyrazoline derivatives containing benzo[d]thiazol-2(3H)-one moiety were synthesized and screened for their inhibitory properties against urease, a clinically important metabolic enzyme. In vitro enzyme inhibition studies revealed that all pyrazolines (7.21-87.77 µM) were more potent than the standard inhibitor acetohydroxamic acid (251.74 µM) against the urease enzyme. Most notably, compound 2m, which is more active than the other compounds in vitro and molecular docking studies, showed a significant inhibition potential and efficient IC50 values (7.21±0.09 µM) and in silico inhibition constant (0.11 µM). Furthermore, molecular dynamics (MD) simulation analysis suggests that the binding stability of urease enzyme and compound 2m were stably maintained during the 100 ns simulation time. Compound 2m also exhibited good physicochemical and pharmacokinetic parameters. The overall results of urease inhibition have indicated that these pyrazoline derivative compounds can be further optimized and developed for the discovery of novel urease inhibitors.

Smart soil grouting using innovative urease-producing bacteria and low cost materials.

AIMS: Calcium carbonate is a biomineral whose precipitation could be mediated by ureolytic bacteria and contributes in strengthening of sandy soils. The type of bacteria and grade of reagents have significant influence on microbially induced calcite precipitation (MICP). In the present study, factorial experiments based on these two factors were designed to determine their potential on MICP process, taking into consideration the economic advantages while giving quality results as well. METHODS AND RESULTS: For the first time, Alkalibacterium iburiense strain EE1 (GenBank accession no. MF355369.1) is reported for its biogrouting activity. Optimum growth conditions for MICP treatments were pH (9·56 ± 0·021), EC (44·7 ± 0·057 mS cm-1 ), OD600 (2·04 ± 0·015), NH4 + concentration (487·06 ± 1·021 mmol l-1 ), and urease activity (20·0 ± 0·75 mmol l-1 urea hydrolysed min-1 ) after 72-h incubation. Statistical analysis comparing the growth in technical-grade medium prepared in tap water and analytical-grade medium prepared in deionized water showed no significant differences (P = 1·0) in biomass and urease activity. In contrast to previous studies, the current approach could reduce the bacterial culture and cementation solution ratio by about 50%, using a simple surface percolation method with staged injection instead of parallel injection to treat different sand columns. Using fixation solution could immobilize the bacteria over the full length of columns for better strength improvement. The unconfined compressive strength ranged between 0·64 to 2·11 kg cm-2 , and the corresponding CaCO3 contents 5·7-38·5%. The scanning electron microscope images indicated that the precipitated CaCO3 by bacteria was stable calcite. CONCLUSIONS: Alkalibacterium iburiense and technical-grade reagents under nonsterile conditions are satisfactory consolidating agents for sandy soils. SIGNIFICANCE AND IMPACT OF THE STUDY: This approach is considered eco-friendly and cost-effective for future scale-up applications in various geotechnical engineering.

Synthesis, crystal structure and biological evaluation of new phosphoramide derivatives as urease inhibitors using docking, QSAR and kinetic studies.

In an attempt to achieve a new class of phosphoramide inhibitors with high potency and resistance to the hydrolysis process against urease enzyme, we synthesized a series of bisphosphoramide derivatives (01-43) and characterized them by various spectroscopic techniques. The crystal structures of compounds 22 and 26 were investigated using X-ray crystallography. The inhibitory activities of the compounds were evaluated against the jack bean urease and were compared to monophosphoramide derivatives and other known standard inhibitors. The compounds containing aromatic amines and their substituted derivatives exhibited very high inhibitory activity in the range of IC50 = 3.4-1.91 × 10-10 nM compared with monophosphoramides, thiourea, and acetohydroxamic acid. It was also found that derivatives with PO functional groups have higher anti-urease activity than those with PS functional groups. Kinetics and docking studies were carried out to explore the binding mechanism that showed these compounds follow a mixed-type mechanism and, due to their extended structures, can cover the entire binding pocket of the enzyme, reducing the formation of the enzyme-substrate complex. The quantitative structure-activity relationship (QSAR) analysis also revealed that the interaction between the enzyme and inhibitor is significantly influenced by aromatic rings and PO functional groups. Collectively, the data obtained from experimental and theoretical studies indicated that these compounds can be developed as appropriate candidates for urease inhibitors in this field.

Selection of a fully human single domain antibody specific to Helicobacter pylori urease.

Helicobacter pylori bacteria are involved in gastroduodenal disorders, including gastric adenocarcinoma. Since the current therapies encounter with some significant shortcomings, much attention has been paid to the development of new alternative diagnostic and treatment modalities such as immunomedicines to target H. pylori. Having used phage display technology, we isolated fully humane small antibody (Ab) fragment (VL) against the Flap region of urease enzyme of H. pylori to suppress its enzymatic activity. Solution biopanning (SPB) and screening process against a customized biotinylated peptide corresponding to the enzyme Flap region resulted in the selection of VL single domain Abs confirmed by the enzyme-linked immunosorbent assay (ELISA), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and Western blotting. The selected Ab fragments showed a high affinity with a KD value of 97.8 × 10-9 and specificity to the enzyme with high inhibitory impact. For the first time, a VL single domain Ab was isolated by SPB process against a critical segment of H. pylori urease using a diverse semi-synthetic library. Based on our findings, the selected VL Ab fragments can be used for the diagnosis, imaging, targeting, and/or immunotherapy of H. pylori. Further, Flap region shows great potential for vaccine therapy.

5-Acetyl-6-methyl-4-aryl-3,4-dihydropyrimidin-2(1H)-ones: As potent urease inhibitors; synthesis, in vitro screening, and molecular modeling study.

5-Acetyl-6-methyl-4-aryl-3,4-dihydropyrimidin-2(1H)-ones 1-43 were synthesized in a "one-pot" three component reaction and structurally characterized by various spectroscopic techniques such as 1H, 13C NMR, EI-MS, HREI-MS, and IR. All compounds were evaluated for their in vitro urease inhibitory activity. It is worth mentioning that except derivatives 1, 11, 12, and 14, all were found to be more potent than the standard thiourea (IC50 = 21.25 ±â€¯0.15 µM) and showed their urease inhibitory potential in the range of IC50 = 3.70 ±â€¯0.5-20.14 ±â€¯0.1 µM. Structure-activity relationship (SAR) was rationalized by looking at the varying structural features of the molecules. However, molecular modeling study was performed to confirm the binding interactions of the molecules (ligand) with the active site of enzyme.

Robust Synthesis of Ciprofloxacin-Capped Metallic Nanoparticles and Their Urease Inhibitory Assay.

The fluoroquinolone antibacterial drug ciprofloxacin (cip) has been used to cap metallic (silver and gold) nanoparticles by a robust one pot synthetic method under optimized conditions, using NaBH4 as a mild reducing agent. Metallic nanoparticles (MNPs) showed constancy against variations in pH, table salt (NaCl) solution, and heat. Capping with metal ions (Ag/Au-cip) has significant implications for the solubility, pharmacokinetics and bioavailability of fluoroquinolone molecules. The metallic nanoparticles were characterized by several techniques such as ultraviolet visible spectroscopy (UV), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) methods. The nanoparticles synthesized using silver and gold were subjected to energy dispersive X-ray tests in order to show their metallic composition. The NH moiety of the piperazine group capped the Ag/Au surfaces, as revealed by spectroscopic studies. The synthesized nanoparticles were also assessed for urease inhibition potential. Fascinatingly, both Ag-cip and Au-cip NPs exhibited significant urease enzyme inhibitory potential, with IC50 = 1.181 ± 0.02 µg/mL and 52.55 ± 2.3 µg/mL, compared to ciprofloxacin (IC50 = 82.95 ± 1.62 µg/mL). MNPs also exhibited significant antibacterial activity against selected bacterial strains.

Exploring biological activities of novel Schiff bases derived from amlodipine and in silico molecular modeling studies.

Aim: Calcium channel antagonists are of considerable interest in treating elevated blood pressure and its pathologies.Materials & methods: Schiff base derivatives of amlodipine were produced to check its urease inhibition potentials as well antibacterial and antioxidant activities. Structural illustration along with chemical characterization were achieved by spectral techniques (1H NMR, FTIR, 13C NMR) and docking studies also performed.Results & conclusion: 3g displayed remarkable anti-hypertensive activity compared with parent drug. 3b, 3f and 3g showed urease inhibition potentials. These compounds can aid as lead for further investigations since they exhibited comparable or superior interactions.

[Box: see text].

A mini review of enzyme-induced calcite precipitation (EICP) technique for eco-friendly bio-cement production.

This paper has presented a mini review of previously published articles dealing with bio-cement production using enzyme-induced calcite precipitation (EICP) technique. EICP is a biological, sustainable, and natural way of producing calcite without the direct involvement of microorganisms from urea and calcium chloride using urease enzyme in water-based solution with minimum energy consumption and eco-friendly. Calcite is a renewable bio-material that acts as a binder to improve the mechanical properties of soils like strength, stiffness, and water permeability. EICP has many real applications such as fugitive duct control with low cost comparing with water application or pouring, self-healing cracked concretes, and upgrade or change the low-volume road surfaces that are difficult for road constructions. The crystal structure of finally produced calcium carbonate (CaCO3), calcite is affected by the source of calcium ion; the calcite produced from calcium chloride has a rhombohedral crystal structure. The urease enzyme used for EICP applications could be produced in a laboratory-scale from different plant species, bacteria, some yeasts, fungi, tissues of humans, and invertebrates. Nevertheless, urease enzyme produced from jack beans has showed urease enzyme activity around 2700-3500U/g, and the tendency to replace the urease enzyme found in the global market. All urease enzymes have 12-nm size, and this smaller size makes EICP preferable for all types of soil or sands including fine and silt sands.

Investigation of a set of flavonoid compounds as Helicobacter pylori urease inhibitors: insights from in silico studies.

Helicobacter pylori (H. pylori) is a spiral, microaerophilic gram-negative bacterium, which is associated with the destruction of the lining of the stomach, leads to chronic inflammation of the stomach, which can cause stomach and duodenal ulcers. The problems caused by the treatment with antibiotics have caused researchers to use new approaches to treat infections caused by H. pylori, among them specific treatments with flavonoids. Urease enzyme, as one of the most important pathogenic and antigenic factors of this bacterium, is a suitable target for this purpose. In this study, the inhibitory effect of flavonoid compounds compared to acetohydroxamic acid on H. pylori urease enzyme was evaluated using molecular modeling methods. First, the interaction of flavonoids with urease enzyme compared with acetohydroxamic acid was investigated by molecular docking method to produce efficient docking poses. Then the physicochemical properties and toxicity of the best flavonoid compounds were analyzed using the swissadme server. Also, molecular dynamics calculations were performed to precisely understand the interactions between ligands and protein. The results of this study show that all the investigated flavonoid compounds are capable of inhibiting H. pylori urease. Among these compounds, six compounds chrysin, galangin, kaempferol, luteolin, morin and quercetin showed a greater tendency to bind to urease, compared to the acetohydroxamic acid inhibitor. These compounds are desirable in terms of physicochemical properties. This study also revealed that the flavonoids with their hydroxyl groups (-OH) play an important role during bond formation with amino acids Ala278, Ala169, His314, Asp362 and Asn168. Therefore, flavonoid compounds, due to their suitable location in the active site of the urease, create a more effective inhibition than the chemical drug acetohydroxamic acid and can be suitable candidates for the treatment of Helicobacter pylori under in vitro and in vivo investigations.Communicated by Ramaswamy H. Sarma.

Structural and Functional Analysis of Urease Accessory Protein E from Vancomycin-Resistance Staphylococcus aureus MU50 Strain.

BACKGROUND: An increasing prevalence of biofilm forming strains by vancomycinresistance Staphylococcus aureus (VRSA) is one of the most important causes of antimicrobial resistance. VRSA possesses various regulatory factors to form and sustain biofilm in biotic or abiotic conditions. Among them, ureolytic activity is an important factor in the stabilization of biofilms by neutralizing the acidic environment. Various urease accessory proteins are required to activate the urease enzyme inside the biofilm. OBJECTIVE: To optimize the cloning, expression and purification of urease accessory protein E from VRSA for determination of the secondary structure, and functional characterization by using Berthelot's method. METHODS: BAB58453.1 gene (which encodes possible urease accessory protein E), having 38% similarity to Bacillus pasteurii UreE protein, was cloned, expressed, and purified by single-step affinity chromatography for performing secondary structural studies using circular dichroism spectroscopy, and functional analysis using Berthelot's and crystal violet assay. RESULTS: Structure elucidation using NMR and circular dichroism spectroscopy techniques revealed that UreE protein has a partially foldedα-helical structure. Using Berthelot's method, it was identified that the purified UreE protein has enhanced urease enzyme activity, in comparison to the control. From the results of Berthelot's and crystal violet assays, it was deduced that the selected gene (UreE protein) plays a key role in enhancing urease enzyme activity and contributes to biofilm stability. CONCLUSION: Structural studies on VRSA urease accessory proteins could aid in the identification of new drug targets or the development of effective antibiofilm strategies (in combination with other drug targets) against infections caused by biofilm-producing strains.

The Effect of Calcium Source on Pb and Cu Remediation Using Enzyme-Induced Carbonate Precipitation.

Heavy metal contamination not only causes threat to human health but also raises sustainable development concerns. The use of traditional methods to remediate heavy metal contamination is however time-consuming, and the remediation efficiency may not meet the requirements as expected. The present study conducted a series of test tube experiments to investigate the effect of calcium source on the lead and copper removals. In addition to the test tube experiments, numerical simulations were performed using Visual MINTEQ software package considering different degrees of urea hydrolysis derived from the experiments. The remediation efficiency degrades when NH4 + and OH- concentrations are not sufficient to precipitate the majority of Pb2+ and Cu2+. It also degrades when CaO turns pH into highly alkaline conditions. The numerical simulations do not take the dissolution of precipitation into account and therefore overestimate the remediation efficiency when subjected to lower Pb(NO3)2 or Cu(NO3)2 concentrations. The findings highlight the potential of applying the enzyme-induced carbonate precipitation to lead and copper remediations.

Molecular dynamics simulations, molecular docking, and kinetics study of kaempferol interaction on Jack bean urease: Comparison of extended solvation model.

Since the urease enzyme creates gastric cancer, peptic ulcer, hepatic coma, and urinary stones in millions of people worldwide, it is essential to find strong inhibitors to help patients. Natural products are well known for their beneficial effects on health and efforts are being made to isolate the ingredients, the so-called flavonoids. Flavonoids are now considered as an indispensable component in a variety of nutraceutical, pharmaceutical, and cosmetic applications. Kaempferol (KPF) is an antioxidant found in many fruits and vegetables. Many reports have explained the significant effects of dietary KPF in reducing the risk of chronic diseases such as cancer, ischemia, stroke, and Parkinson's. The current study aimed at investigating the inhibitory impact of KPF on Jack bean urease (JBU) using molecular dynamics (MD) simulations and molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) calculations to confirm the results obtained from isothermal titration calorimetry (ITC), extended solvation model, and docking software. In addition, UV-VIS spectrophotometry was used to study the kinetics of urease inhibition. Calorimetric and spectrophotometric determinations of the kinetic parameters of this inhibition indicate the occurrence of a reversible and noncompetitive mode. Also, the docking and MD results indicated that the urease had well adapted to the kaempferol in the binding pocket, thereby forming a stable complex. Kaempferol displayed low binding energy during MMPBSA calculations. The inhibitory potential of kaempferol was confirmed by experimental and simulation data, but in vivo investigations are also recommended to validate our results.

Effects of the Urease Concentration and Calcium Source on Enzyme-Induced Carbonate Precipitation for Lead Remediation.

Heavy metal contamination during the rapid urbanization process in recent decades has notably impacted our fragile environments and threatens human health. However, traditional remediation approaches are considered time-consuming and costly, and the effect sometimes does not meet the requirements expected. The present study conducted test tube experiments to reproduce enzyme-induced carbonate precipitation applied to lead remediation under the effects of urease concentration and a calcium source. Furthermore, the speciation and sequence of the carbonate precipitation were simulated using the Visual MINTEQ software package. The results indicated that higher urease concentrations can assure the availability of CO3 2- during the enzyme-induced carbonate precipitation (EICP) process toward benefiting carbonate precipitation. The calcium source determines the speciation of carbonate precipitation and subsequently the Pb remediation efficiency. The use of CaO results in the dissolution of Pb(OH)2 and, therefore, discharges Pb ions, causing some difficulty in forming the multi-layer structure of carbonate precipitation and degrading Pb remediation. The findings of this study are useful in widening the horizon of applications of the enzyme-induced carbonate precipitation technology to heavy metal remediation.

Advances in Enzyme Induced Carbonate Precipitation and Application to Soil Improvement: A Review.

Climate change and global warming have prompted a notable shift towards sustainable geotechnics and construction materials within the geotechnical engineer's community. Earthen construction materials, in particular, are considered sustainable due to their inherent characteristics of having low embodied and operational energies, fire resistance, and ease of recyclability. Despite these attributes, they have not been part of the mainstream construction due to their susceptibility to water-induced deterioration. Conventional soil improvement techniques are generally expensive, energy-intensive, and environmentally harmful. Recently, biostabilization has emerged as a sustainable alternative that can overcome some of the limitations of existing soil improvement methods. Enzyme-induced carbonate precipitation (EICP) is a particularly promising technique due to its ease of application and compatibility with different soil types. EICP exploits the urease enzyme as a catalyst to promote the hydrolysis of urea inside the pore water, which, in the presence of calcium ions, results in the precipitation of calcium carbonate. The purpose of this paper is to provide a state-of-the-art review of EICP stabilization, highlighting the potential application of this technique to field problems and identifying current research gaps. The paper discusses recent progress, focusing on the most important factors that govern the efficiency of the chemical reactions and the precipitation of a spatially homogenous carbonate phase. The paper also discusses other aspects of EICP stabilization, including the degree of ground improvement, the prediction of the pore structure of the treated soil by numerical simulations, and the remediation of potentially toxic EICP by-products.

Synthesis of benzoyl hydrazones having 4-hydroxy-3,5-dimethoxy phenyl ring, their biological activities, and molecular modeling studies on enzyme inhibition activities.

Hydrazone compounds have high capacity in terms of antioxidant activity and enzyme inhibition activities such as anticholinesterase, tyrosinase, and urease. In this study, benzoyl hydrazones compounds (7a-7m) were synthesized starting from 3,5-dimethoxy-4-hydroxybenzaldehyde. Antioxidant activity of the synthesized compounds was evaluated. In the ß-carotene-linoleic acid and ABTS cation radical scavenging activities, compounds 7j, 7e, and 7m stood out as the most active compounds, respectively. In the anticholinesterase enzyme inhibition activity results, compound 7f exhibited the best activity against AChE and BChE enzymes in the synthesis series. In addition, molecular docking analysis was performed to understand the inhibition mechanism of the synthesized compounds with target enzymes at the atomic level. In the light of biological activity and in silico studies, it has the potential to guide studies for the development of new drugs for Alzheimer disease in the future.

MICP as a potential sustainable technique to treat or entrap contaminants in the natural environment: A review.

In the last two decades, developments in the area of biomineralization has yielded promising results making it a potentially environmentally friendly technique for a wide range of applications in engineering and wastewater/heavy metal remediation. Microbially Induced Carbonate Precipitation (MICP) has led to numerous patented applications ranging from novel strains and nutrient sources for the precipitation of biominerals. Studies are being constantly published to optimize the process to become a promising, cost effective, ecofriendly approach when compared with the existing traditional remediation technologies which are implemented to solve multiple contamination/pollution issues. Heavy metal pollution still poses a major threat towards compromising the ecosystem. The removal of heavy metals is of high importance due to their recalcitrance and persistence in the environment. In that perspective, this paper reviews the current and most significant discoveries and applications of MICP towards the conversion of heavy metals into heavy metal carbonates and removal of calcium from contaminated media such as polluted water. It is evident from the literature survey that although heavy metal carbonate research is very effective in removal, is still in its early stages but could serve as a solution if the microorganisms are stimulated directly in the heavy metal environment.

Synthesis of Urease Inhibitory 2, 4-bis (4-cyanobenzyl)glycoluril using Sandmeyer Reaction and Density Functional Theory Investigation.

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.