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Three novel deep-red to near-infrared (DR to NIR) emitters based on mononuclear and dinuclear ruthenium(II) complexes with bulky structures were presented herein. For the first time, the unusual effects of metal coordination mode on the electroluminescence properties of a binuclear emitter were investigated. Unexpectedly, the mononuclear complexes showed superior performance in deep-red light-emitting electrochemical cells (DR-LEC) compared to the dinuclear complex. Likewise, substituting various ancillary ligands improved the radiance and lifetime of devices by 2.5 and 1.5 times, respectively. To the best of our knowledge, the obtained efficiency is among the best reported to date for DR-LECs based on ruthenium polypyridyl complexes.
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A novel imine-linked COF is synthesized by the condensation of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (TAPT) and 2-hydroxy-5-methoxyisophthalaldehyde (HMIPA) under solvothermal conditions. This COF adsorbs preferentially the neutral dye Neutral Red (NR) over the positively charged dye Methylene Blue (MB) at pH 7, and the negatively charged Methyl Orange (MO) over the positively charged Methylene Blue (MB) at pH 3. The maximum adsorption capacities (qe) obtained within very short times (11-60 min) under optimized conditions were 108, 185 and 429 mg.g-1 for the MB, MO, and NR dyes, respectively. These adsorptions obey the Langmuir isotherm and pseudo-second-order kinetics. The prepared TAPT-HMIPA-COF is used successfully for the removal of the dyes from real water and treated wastewater samples. The adsorption data, BET, FTIR, and zeta potential measurements show that the electrostatic, π-π stacking and hydrogen bond interactions are responsible for the adsorption of organic dyes on the surface of the prepared COF. Due to recyclability, high capacity and efficiency for the adsorption of positive, negative and neutral organic dyes, this COF can be considered promising for simultaneous removal of various dyes from aqueous solutions at adjusted pHs.
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In this research, we utilized an efficient approach to synthesize superparamagnetic graphene oxide (SPGO) rapidly in a one-pot method using microwave irradiation of graphene oxide (GO), urea, and Fe(III) ion. Tannic acid (TA) was introduced to the surface of SPGO through a straightforward and eco-friendly process. Methods were devised to furnish GO nanosheets and modify their surfaces with TA in an environmentally friendly manner. Two series of nanosheets, namely, SPGO/TA-COOH and SPGO/TA-IM, were engineered on the surface and used for immobilizing lipase enzyme. Through various analytical tools, the unique biocatalysts SPGO/TA-COOH/L and SPGO/TA-IM/L were confirmed. These biocatalysts exhibited enhanced stability at high temperatures and pH levels compared with free lipase. They also demonstrated prolonged storage stability and reusability over four months and seven cycles, respectively. Furthermore, the catalytic activity of immobilized lipase showed minimal impairment based on kinetic behavior analysis. The kinetic constants of SPGO/TA-IM/L were determined as Vmax = 0.24 mM min-1, Km = 0.224 mM, and kcat = 0.8 s-1. Additionally, the efficiency of biocatalysts for biodiesel production from palmitic acid was studied, focusing on various reaction parameters, such as temperature, alcohol to palmitic acid molar ratio, water content, and lipase quantity. The esterification reaction of palmitic acid with methanol, ethanol, and isopropanol was tested in the presence of SPGO/TA-COOH/L and SPGO/TA-IM/L, and the corresponding esters were obtained with a yield of 30.6-91.6%.
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Biocombustíveis , Enzimas Imobilizadas , Grafite , Lipase , Propriedades de Superfície , Grafite/química , Lipase/metabolismo , Lipase/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Teste de Materiais , Taninos/química , Tamanho da Partícula , Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/metabolismo , Nanoestruturas/químicaRESUMO
Background: Antibiotic resistance in Klebsiella pneumoniae isolates, particularly resistance to colistin, has become a growing concern. This study seeks to investigate the upregulation of specific genes (pmrA, pmrB, pmrC, phoQ, phoP, and arnT) that contribute to colistin resistance in K. pneumoniae isolates collected from human clinical samples in Tehran, Iran. Methods: Thirty eight K. pneumoniae isolates were obtained and subjected to antibiotic susceptibility testing, as well as evaluation for phenotypic AmpC and ESBL production according to CLSI guidelines. The investigation of antibiotic resistance genes was conducted using polymerase chain reaction (PCR), whereas the quantification of colistin resistance related genes expressions was performed via Real-Time PCR. Results: The highest and lowest antibiotics resistance were observed for cefotaxime 33 (86.8%) and minocycline 8 (21.1%), respectively. Twenty-four (63.2%) and 31 (81.6%) isolates carried AmpC and ESBLs, respectively. Also, antibiotic resistance genes containing blaNDM, blaIMP, blaVIM, blaSHV, blaTEM, blaCTXM, qnrA, qnrB, qnrS, and aac(6')-Ib were detected in K. pneumoniae isolates. Only 5 (13.1%) isolates were resistant to colistin and the MIC range of these isolates was between 4 and 64 µg ml-1. Upregulation of the pmrA, pmrB, pmrC, phoQ, phoP, and arnT genes was observed in colistin-resistant isolates. The colistin-resistant isolates were found to possess a simultaneous presence of ESBLs, AmpC, fluoroquinolone, aminoglycoside, and carbapenem resistant genes. Conclusions: This study reveals escalating antibiotic resistance in K. pneumoniae, with notable coexistence of various resistance traits, emphasizing the need for vigilant surveillance and innovative interventions.
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Legionella pneumophila can be transmitted to people, especially immunocompromised patients, via hospital water pipe systems and cause severe pneumonia. The aim of our study was to investigate the presence of major virulence factor genes, ability of biofilms formation, and correlation between presence of Legionella isolates and temperature, pH, and residual chlorine of water. Hundred water samples were collected from nine hospitals in Tehran, Iran. Temperature, pH, and residual chlorine were determined during sampling. Different virulence genes and the ability to form biofilms were subsequently analyzed among the L. pneumophila isolates. Results showed that 12 (12%) samples were positive in culture method and all of the isolates were positive as L. pneumophila species (mip). A correlation was found between Legionella culture positivity and temperature and pH of water, but there was no significant correlation between residual chlorine of water samples and the presence of Legionella. The isolation of Legionella rate in summer and spring was higher than winter and autumn. Twelve (100%) isolates were positive for mip genes, 9 (75%) for dot genes, 8 (66.66%) for hsp, 6 (50%) for lvh, and 4 (33.33%) for rtx. All of the isolates displayed strong ability for biofilm production every three days. Two of these isolates (16.6%) displayed weak ability to form biofilm on the first day of incubation. This study revealed that water sources in hospitals were colonized by virulent Legionella and should be continuously monitored to avoid elevated concentrations of Legionella with visible biofilm formation.
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Legionella pneumophila , Legionella , Humanos , Legionella pneumophila/genética , Virulência/genética , Cloro/farmacologia , Irã (Geográfico) , Biofilmes , HospitaisRESUMO
Organometal halide perovskite solar cells have reached a high power conversion efficiency of up to 25.8% but suffered from poor long-term stability against environmental factors such as ultraviolet irradiation and humidity of the environment. Herein, two different multifunctional transparent coatings containing AZO and ZnO porous UV light absorbers were employed on the front of the PSCs. This strategy is designed to improve the long-term stability of PSCs against UV irradiation. Moreover, the provided coatings exhibit two additional roles, including self-cleaning and high wear resistance. In this regard, AZO coating showed higher wear resistance compared to the ZnO coating. The photocatalytic self-cleaning properties of these prepared coatings make them stable against environmental pollutants. Furthermore, appropriate mechanical properties such as high hardness and low coefficient of friction that leads to high resistance against wear are other features of these coatings. The devices with AZO/Glass/FTO/meso-TiO2/Perovskite/spiro/Au and ZnO/Glass/FTO/meso-TiO2/Perovskite/spiro/Au configurations maintained 40% and 30% of their initial performance for 100 h during 11 days (9 h per day) against the UV light with the high intensity of 50 mW cm-2 which is due to higher absorption of AZO compared with ZnO in the ultraviolet region. Since AZO has a higher light transmission in the visible region in comparison to ZnO, perovskite cells with AZO protective layers have higher efficiency than perovskite cells with ZnO layers. It is worth noting that the mentioned features make these coatings usable for cover glass in all types of solar cells.
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PURPOSE: Over the last decade, surgery rates have risen alarmingly, and surgical-site infections are expanding these concerns. In spite of advances in infection control practices, surgical infections continue to be a significant cause of death, prolonged hospitalization, and morbidity. As well as the presence of bacterial infections and their antibiotic resistance, biofilm formation is one of the challenges in the treatment of surgical wounds. METHODS: This review article was based on published studies on inpatients and laboratory animals receiving phage therapy for surgical wounds, phage therapy for tissue and bone infections treated with surgery to prevent recurrence, antibiotic-resistant wound infections treated with phage therapy, and biofilm-involved surgical wounds treated with phage therapy which were searched without date restrictions. RESULTS: It has been shown in this review article that phage therapy can be used to treat surgical-site infections in patients and animals, eliminate biofilms at the surgical site, prevent infection recurrence in wounds that have been operated on, and eradicate antibiotic-resistant infections in surgical wounds, including multi-drug resistance (MDR), extensively drug resistance (XDR), and pan-drug resistance (PDR). A cocktail of phages and antibiotics can also reduce surgical-site infections more effectively than phages alone. CONCLUSION: In light of these encouraging results, clinical trials and research with phages will continue in the near future to treat surgical-site infections, biofilm removal, and antibiotic-resistant wounds, all of which could be used to prescribe phages as an alternative to antibiotics.
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Infecções Bacterianas , Terapia por Fagos , Ferida Cirúrgica , Humanos , Animais , Bactérias , Infecção da Ferida Cirúrgica/prevenção & controle , Infecções Bacterianas/prevenção & controle , Antibacterianos/uso terapêuticoRESUMO
In this research, a new Lewis acid-based deep eutectic solvent (LA-DES) was synthesized using diphenhydramine hydrochloride and CoCl2·6H2O, (2[HDPH]:CoCl42-), and identified by FT-IR and 1HNMR techniques. The physicochemical properties of this LA-DES, such as thermal behavior, thermal stability, and solubility in common solvents were also investigated. The catalytic ability of 2[HDPH]:CoCl42- was ascertained in the efficient synthesis of a novel array of thiadiazolo[2,3-b]quinazolin-6-one scaffolds via a one-pot three-component reaction of dimedone/1,3-cyclohexanedione, aldehydes, and 5-aryl-1,3,4-thiadiazol-2-amines/3-(5-amino-1,3,4-thiadiazol-2-yl)-2H-chromen-2-one under solvent-free conditions. This catalyst was also successfully utilized for the synthesis of mono- and bis-thiadiazolo[2,3-b]quinazolin-6-ones from dialdehydes or bis-1,3,4-thiadiazol-2-amine. The simplicity of enforcement, short reaction time, avoidance of toxic organic solvents, scalability of the synthesis procedure, excellent atom economy, high reaction mass efficiency, and low E-factor are other outstanding advantages of this newly developed method. Furthermore, due to the convenient recovery and reuse of LA-DES, this protocol is economically justified and environmentally friendly.
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Defending against antibiotic-resistant infections is similar to fighting a war with limited ammunition. As the new century unfolded, antibiotic resistance became a significant concern. In spite of the fact that phage treatment has been used as an effective means of fighting infections for more than a century, researchers have had to overcome many challenges of superbug bacteria by manipulating phages and producing engineered enzymes. New enzymes and phages with enhanced properties have a significant impact on the ability to fight antibiotic-resistant infections, which is considered a window of hope for the future. This review, therefore, illustrates not only the challenges caused by antibiotic resistance and superbug bacteria but also the engineered enzymes and phages that are being developed to solve these issues. Our study found that engineered phages, phage proteins, and enzymes can be effective in treating superbug bacteria and destroying the biofilm caused by them. Combining these engineered compounds with other antimicrobial substances can increase their effectiveness against antibiotic-resistant bacteria. Therefore, engineered phages, proteins, and enzymes can be used as a substitute for antibiotics or in combination with antibiotics to treat patients with superbug infections in the future.
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Bacteriófagos , Humanos , Bactérias , Antibacterianos , BiofilmesRESUMO
In recent decades, the expansion of multi and extensively drug-resistant (MDR and XDR) bacteria has reached an alarming rate, causing serious health concerns. Infections caused by drug-resistant bacteria have been associated with morbidity and mortality, making tackling bacterial resistance an urgent and unmet challenge that needs to be addressed properly. Endolysins are phage-encoded enzymes that can specifically degrade the bacterial cell wall and lead to bacterial death. There is remarkable evidence that corroborates the unique ability of endolysins to rapidly digest the peptidoglycan particular bonds externally without the assistance of phage. Thus, their modulation in therapeutic approaches has opened new options for therapeutic applications in the fight against bacterial infections in the human and veterinary sectors, as well as within the agricultural and biotechnology areas. The use of genetically engineered phage enzymes (EPE) promises to generate endolysin variants with unique properties for prophylactic and therapeutic applications. These approaches have gained momentum to accelerate basic as well as translational phage research and the potential development of therapeutics in the near future. This review will focus on the novel knowledge into EPE and demonstrate that EPE has far better performance than natural endolysins and phages in dealing with antibiotic-resistant infections. Therefore, it provides essential information for clinical trials involving EPE.
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Infecções Bacterianas , Bacteriófagos , Humanos , Bacteriófagos/metabolismo , Antibacterianos/química , Endopeptidases/química , Infecções Bacterianas/tratamento farmacológico , Bactérias/metabolismo , Peptidoglicano/metabolismo , Peptidoglicano/uso terapêuticoRESUMO
In this study, a lactose fatty acid ester was enzymatically synthesised using immobilized Candida rugosa lipase (CRL). Its anticancer property against K562 leukemia and HeLa cancer cells was carefully investigated. In the first step, a de novo strategy was applied to encapsulate CRL into a microporous zeolite imidazolate framework called ZIF-8. Various characterization techniques including powder X-ray diffraction, Fourier transform infrared spectroscopy, N2 adsorption-desorption, field-emission scanning electron microscopy and thermogravimetric analysis were used to prove the successful encapsulation of CRL molecules during the formation of ZIF-8 crystals with an enzyme loading of 98% of initial CRL. The effect of various factors such as pH and temperature, affecting the enzymatic activity and reusability of the CRL@ZIF-8 composite were assessed against the free enzyme. Additionally, enzyme catalysis parameters, such as Km and Vmax, were also assessed. The obtained biocatalyst showed excellent activity in a wide pH range of 2-9 and a temperature range of 30-60 °C. According to the experimental results, the CRL@ZIF-8 composite maintained about 63% of its initial activity after 6 cycles of use. In the next step, the synthesized catalyst was applied for the synthesis of lactose caprate via enzymatic esterification of lactose with capric acid. Further experiments were performed to obtain the cytotoxicity profile of the new derivative. The growth inhibitory effect of the produced lactose caprate on K562 leukemia and HeLa cancer cells determined by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed its potential anticancer effects against both cell lines (IC50, 49.6 and 57.2 µg mL-1). Our results indicate that lactose caprate might be a promising candidate for further studies on K562 leukemia and HeLa cancer cells owing to its possible therapeutic usefulness.
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Aminopropyl-1,3,5-triazine-2,4-diphosphonium tetrachloroferrate immobilized on halloysite nanotubes [(APTDP)(FeCl4)2@HNT] was prepared and fully characterized using different techniques such as FT-IR, thermogravimetric analysis (TGA), SEM/EDX, elemental mapping, TEM, ICP-OES, and elemental analysis (EA). This nanocatalyst was found to be highly effective for synthesis of various benzothiazole derivatives in excellent yields under solvent-free conditions. Furthermore, bis- and tris-benzothiazoles were smoothly synthesized from dinitrile and trinitrile in the presence of this catalytic system. High yields and purity, easy work up procedure, high catalytic activity (high TON and TOF) and easy recovery and reusability of the catalyst make this method a useful and important addition to the present methodologies for preparation of these vital heterocyclic compounds.
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Background: Radiotherapy is a crucial treatment for most malignancies. However, it can cause several side effects, including the development of secondary malignancies due to radiation-induced genomic instability (RIGI). The aim of this study was to evaluate genomic instability in human mesenchymal stem cells (hMSCs) at different X-ray radiation doses. Additionally, the study aimed to examine the relative expression of certain genes involved in DNA repair, proto-oncogenes, and tumor suppressor genes. Methods: After extracting, characterizing, and expanding hMSCs, they were exposed to X-ray beams at doses of 0, 0.5, 2, and 6 Gy. Nuclear alterations were evaluated through the cytokinesis-block micronucleus (CBMN) assay at 2, 10, and 15 days postirradiation. The expressions of BRCA1, BRCA2, TP53, Bax, Bcl2, and KRAS genes were analyzed 48 hr after irradiation to evaluate genomic responses to different radiation doses. Results: The mean incidence of micronuclei, nucleoplasmic bridges, and nuclear buds was 4.8 ± 1.6, 47.6 ± 6, and 18 ± 2.6, respectively, in the nonirradiated group 48 hr after the fourth passage, per 1,000 binucleated cells. The incidence of micronuclei in groups exposed to 0.5, 2, and 6 Gy of radiation was 14.3 ± 4.9, 32.3 ± 6.5, and 55 ± 9.1, respectively, 48 hr after irradiation. The expression levels of the BRCA2, Bax, TP53, and KRAS genes significantly increased after exposure to 6 Gy radiation compared to the control groups. However, there was no significant increase in BRCA1 and Bcl2 gene expression in our study. Conclusion: This study demonstrated significant nuclear alterations in the 10 days postirradiation due to the RIGIs that they inherited from their irradiated ancestral cells. While chromosomal instability is a prevalent event in malignant cells, so it seems necessary to optimize radiotherapy treatment protocols for tissues that contain stem cells, especially with IMRT, which delivers a low dose to a larger volume of tissues.
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Objective: Ephedra herbs are the only extant genus in its family, Ephedraceae, and order, Ephedrales. It has been prescribed in traditional medicine for improving headaches and respiratory infections. On the other hand, because the coronavirus disease 2019 (COVID-19) causes respiratory problems and COVID-19 pandemic is the most widespread outbreak that has affected humanity in the last century, the current review aims using literature search to investigate the effects of the Ephedra herbs compounds on COVID-19 to supply a reference for its clinical application in the inhibition and remedy of COVID-19. Materials and Methods: This review was performed using articles published in various databases, including Web of Science, PubMed, Scopus, and Google Scholar, without a time limit. For this paper, the following keywords were used: "Ephedra", "coronavirus disease 2019", "COVID-19", "Severe acute respiratory syndrome coronavirus 2" or "SARS CoV 2". Results: The results of this review show that the Ephedra herbs have effectiveness on COVID-19 and its compounds can bind to angiotensin-converting enzyme 2 (ACE2) with a high affinity and act as a blocker and prevent the binding of the virus. Conclusion: Some plants used in traditional medicine, including the Ephedra herbs, with their active compounds, can be considered a candidate with high potential for the control and prevention of COVID-19.
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One of the most tragic events in recent history was the COVID-19 outbreak, which has caused thousands of deaths. A variety of drugs were prescribed to improve the condition of patients, including antiparasitic, antiviral, antibiotics, and anti-inflammatory medicines. It must be understood, however, that COVID-19 is like a tip of an iceberg on the ocean, and the consequences of overuse of antibiotics are like the body of a mountain under water whose greatness has not yet been determined for humanity, and additional study is needed to understand them. History of the war between microbes and antimicrobial agents has shown that microbes are intelligent organisms that win over antimicrobial agents over time through many acquired or inherent mechanisms. The key terms containing "COVID-19," "Severe acute respiratory syndrome coronavirus-2," "SARS-CoV2," "Antibiotic Resistance," "Coronavirus," "Pandemic," "Antibiotics," and "Antimicrobial Resistance" were used for searching in PubMed, Scopus, and Google Scholar databases. The COVID-19 pandemic has resulted in an increased prescription of antibiotics. Infections caused by secondary or co-bacterial infections or beneficial bacteria in the body can be increased as a result of this amount of antibiotic prescription and exposure to antibiotics. Antibiotic resistance will likely pose a major problem in the future, especially for last resort antibiotics. In order to address the antibiotic resistance crisis, it is imperative that researchers, farmers, veterinarians, physicians, public and policymakers, pharmacists, other health and environmental professionals, and others collaborate during and beyond this pandemic.
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Although microbiology and neurology are separate disciplines, they are linked to some infectious and neurological diseases. Today, microbiome is considered as one of the biomarkers of health by many researchers. This has led to the association of microbiome changes with many neurological diseases. The natural microbiota has many beneficial properties. If disrupted and altered, it can lead to irreversible complications and many neurological diseases. Therefore, according to previous studies, some preventive and therapeutic complementary therapies can prevent or restore microbiome dysbiosis and inflammation in the nervous system. With our current perception of the microbiological basis for different neurological disorders, both aspects of drug treatment and control of perturbations of the microbiome should be considered, and targeting them simultaneously will likely help to attain favorable results.
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Terapias Complementares , Microbioma Gastrointestinal , Transtornos Mentais , Microbiota , Doenças do Sistema Nervoso , Probióticos , Humanos , Microbioma Gastrointestinal/fisiologia , Transtornos Mentais/prevenção & controle , Doenças do Sistema Nervoso/terapiaRESUMO
Two novel MOF- ethyl cellulose (EC)- based nanocomposites have been designed and synthesized in water by electrospinning and applied for adsorption of congo red (CR) in water. Nano- Zeolitic Imidazolate Framework-67 (ZIF-67), and Materials of Institute Lavoisier (MIL-88A) were synthesized in aqueous solutions by a green method. To enhance the dye adsorption capacity and stability of MOFs, they have been incorporated into EC nanofiber to prepare composite adsorbents. The performance of both composites in the absorption of CR, a common pollutant in some industrial wastewaters, has then been investigated. Various parameters including initial dye concentration, the dosage of the adsorbent, pH, temperature and contact time were optimized. The results indicated 99.8 and 90.9% adsorption of CR by EC/ZIF-67 and EC/MIL-88A, respectively at pH = 7 and temperature at 25 °C after 50 min. Furthermore, the synthesized composites were separated conveniently and successfully reused five times without significant loss of their adsorption activity. For both composites, the adsorption behavior can be explained by pseudo-second-order kinetics, Intraparticular diffiusion and Elovich models demonstrated that the experimental data well matched to the pseudo-second-order kinetics. Intraparticular diffiusion model showed that the adsorption of CR on EC/ZIF-67 and EC/MIL-88a took place in one and two steps, respectively. Freundlich isotherm models and thermodynamic analysis indicated exothermic and spontaneous adsorption.
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The current study deals with the synthesis and characterization of a novel catalyst made from diphenhydramine hydrochloride and CuCl ([HDPH]Cl-CuCl). The prepared catalyst was thoroughly characterized using various techniques, such as 1H NMR, Fourier transform-infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis and derivative thermogravimetry. More importantly, the observed hydrogen bond between the components was proven experimentally. The activity of this catalyst was checked in the preparation of some new derivatives of tetrahydrocinnolin-5(1H)-ones via a multicomponent reaction between dimedone, aromatic aldehydes, and aryl/alkyl hydrazines in ethanol as a green solvent. Also, for the first time, this new homogeneous catalytic system was effectively used for the preparation of unsymmetric tetrahydrocinnolin-5(1H)-one derivatives as well as mono- and bis-tetrahydrocinnolin-5(1H)-ones from two different aryl aldehydes and dialdehydes, respectively. The effectiveness of this catalyst was further confirmed by the preparation of compounds containing both tetrahydrocinnolin-5(1H)-one and benzimidazole moieties from dialdehydes. The one-pot operation, mild conditions, rapid reaction, and high atom economy, along with the recyclability and reusability of the catalyst, are other notable features of this approach.