Synthesis and therapeutic potential of imidazole containing compounds

Green synthesis, characterization, in silico molecular docking and biological evaluation of imidazolylchalcones as promising fungicide/s and nematicide/s

Chalcones are known for their broad biological activities, which can be enhanced by incorporating heterocyclic moieties. Imidazole, recognized for its diverse properties, was introduced into a series of imidazolylchalcone derivatives (3a-3o) synthesized via Claisen-Schmidt condensation of benzaldehydes (2a-2o) and 4-(Imidazol-1-yl) acetophenone (1a) using ultrasonication as a green method. These compounds were characterized by spectroscopic techniques such as 1H-NMR, 13C-NMR, LC-HRMS and evaluated for fungicidal and nematicidal activity. Compound 3 h showed highest fungicidal activity against Rhizoctonia solani (ED₅₀ = 0.69 μg/mL), outperforming commercial hexaconazole (ED₅₀ = 3.57 μg/mL). Compound 3d exhibited the highest activity against Fusarium oxysporum (ED₅₀ = 119.22 μg/mL), while 3f was most effective against Meloidogyne incognita (LC₅₀ = 33.62 μg/mL), though less active than commercial Velum Prime (LC₅₀ = 3.46 μg/mL). The compounds potential activity may results from interactions of electronegative atom with enzyme active sites via hydrogen bonding. Docking studies against fungal cutinase and nematode acetylcholinesterase supported the in-vitro findings. Promising compounds will undergo further in-vivo and field trials for antifungal and antinemic applications and developed a potent molecule.

Excavating medicinal virtues of chalcones to illuminate a new scope in cancer chemotherapy

A common simple scaffold, 1,3-diaryl-2-propen-1-one (also known as chalcone), is present in many important natural products. This scaffold is the backbone of several flavonoids and isoflavonoids. Owing to the simple approachable synthetic strategies and the rigid backbone of chalcone and its derivatives, they have captivated the attention of researchers for several decades. Chalcone and its derivatives possess strong biological activities, viz. anti-tumor activity and anticancer potency. Accordingly, the in vitro and in vivo anticancer activities of several chalcone-based compounds with strong anticancer potential have been identified, which relies on mechanisms such as cell cycle arrest, regulation of autophagy, and induction of apoptosis. Therefore, researchers have successfully introduced chalcone derivatives to achieve enhanced anticancer activity in traditional chemotherapy. Nevertheless, in-depth research on this highly impactful scaffold is lacking to date. Thus, in this review, we shed light on the recent advances in the relatively unexplored scaffolds of chalcone and its derivatives, which have substantial anticancer activities. Furthermore, future perspectives of the mushrooming research on chalcones as potential anticancer agents (therapeutics) are emphasized.

Five-membered heterocycles as promising platforms for molecular logic gate construction

The field of molecular logic gates began thirty years ago with the early pioneers de Silva et al. (A. P. de Silva, H. Q. N. Gunaratne and C. P. McCoy, Nature, 1993, 364, 42) laying the foundation for modern molecular-scale switches and devices. Recent reports of lab-on-a-molecule and molecular calculators (Moleculators) demonstrate the potential of this bottom-up approach. Five-membered heterocycles were central to the first reported logic gates in 1994 and remain valuable scaffolds in the present day. This review provides an overview of logic gate design using Boolean logic, introduces the work of the first pioneers, and highlights recently reported five-membered heterocycle logic gates.

Oxidative Coupling of Guanidines and Isocyanides Catalyzed by Nickel(II): Access to Imidazoline Derivatives with Antibacterial Activity

A novel and concise approach to rare 2,3,5-triamino-imidazole scaffolds via Ni-catalyzed coupling of alkylisocyanides and N,N'-diarylguanidines has been developed. This reaction features include mild conditions (thermal or visible light activation), a wide substrate scope, and high efficiency. The coupling proceeds through a NiII/NiIV catalytic cycle, involving two-electron aerobic oxidation and the sequential insertion of two isocyanide units into Ni-N bonds.Testing these compounds against pathogens of the ESKAPE panel showed their high activity with a minimum inhibitory concentration down to 0.38 μg/mL.

Exploring antibiofilm potential of some new imidazole analogs against C. albicans: synthesis, antifungal activity, molecular docking and molecular dynamics studies

A series of 1, 2, 4, 5-tetrasubstituted imidazole derivatives were synthesized and their antibiofilm potential against Candida albicans was evaluated in vitro. Two of the synthesized derivatives 5e (IC50 = 25 µg/mL) and 5m (IC50 = 6 µg/mL),displayed better antifungal and antibiofilm potential than the standard drug Fluconazole (IC50 = 40 µg/mL) against C. albicans. Based on the in vitro results, we escalated the real time polymerase chain reaction (RT-PCR) analysis to gain knowledge of the enzymes expressed in the generation and maintenance of biofilms and the mechanism of biofilm inhibition by the synthesized analogues. We then investigated the possible interactions of the synthesized compounds in inhibiting agglutinin-like proteins, namely Als3, Als4 and Als6 were prominently down-regulated using in-silico molecular docking analysis against the previously available crystal structure of Als3 and constructed structure of Als4 and Als6 using the SWISS-MODEL server. The stability and energy of the agglutinin-like proteins-ligand complexes were evaluated using molecular dynamics simulations (MDS). According to the 100 ns MDS, all the compounds remained stable, formed a maximum of 3, and on average 2 hydrogen bonds, and Gibb's free energy landscape analysis suggested greater affinity of the compounds 5e and 5m toward Als4 protein.

Synthesis, characterization and in silico studies of novel multifunctional imidazole-thiazole hybrids with potent antimicrobial and anticancer properties

Treating infections remains a significant challenge, driving the ongoing pursuit of novel drug candidates. Heterocyclic compounds, such as those containing imidazole and thiazole rings, are well-known for their diverse therapeutic and pharmaceutical applications. In this study, we designed, synthesized, and characterized a series of six novel compounds incorporating these two five-membered rings. The synthesis involved the reaction of different phenacyl bromides with imidazole-hydrazinecarbothioamide to produce imidazole-thiazole hybrid derivatives, which were confirmed through IR, 1H NMR, 13C NMR, and mass spectrometry analyses. The antimicrobial activities of the derivatives were evaluated against three bacterial strains and one fungal strain using the serial dilution method, with their minimum inhibitory concentrations (MICs) determined. Notably, all the derivatives exhibited moderate antimicrobial activity. Cytotoxicity assessment revealed that derivative 5a was particularly excellent, displaying significant inhibition with an IC50 value of 33.52 μM. Furthermore, molecular docking, ADME, and molecular dynamics simulations were conducted, focusing on the interaction between derivative 5a and the protein (PDB ID: 6LUD) to elucidate the stability of the interaction.

Liquid Metal Particles Decorated by Poly(imidazole-urea) as Versatile Adhesive and Recyclable Inks for Substrate-Irrelevant Direct Writing

Liquid metals (LMs) with fluidity and conductivity are widely applied in flexible electronics. However, the surface patterning of liquid metals (LMs) is restricted by the low adhesion effect on the substrates because of the intrinsic high surface tension. In this study, a versatile adhesive conductive poly(imidazole-urea)/eutectic Ga75.5In24.5 alloy (PIU/EGaIn) ink is proposed by wrapping the EGaIn particles with PIU through metal coordination to realize substrate-independent direct writing. The adhesion of PIU guarantees that the PIU/EGaIn ink can be written smoothly on different substrates, ranging from flexible to rigid and plane to camber. Complex patterns can also be stamped on the substrate by transfer printing. The maximum conductivity of the handwriting trace can reach as high as 1.3 × 106 S/m due to the highly efficient stability of EGaIn particles with a low content of residue PIU. The written circuit demonstrates high stability and maintains constant conductivity after 500 cycles of deformations (folding, bending, and stretching), thanks to the good adhesion effect of PIU with substrates. In addition, the resistance touch sensor was patterned to detect finger contact as a demonstration of potential application. The PIU/EGaIn ink waste can be recycled using an alkaline solution owing to the intrinsic degradability of PIU. This strategy offers a new choice for universal adhesive conductive ink that is suitable for environmentally friendly flexible electronics.

Exploring USFDA-Approved Imidazole-Based Small Molecules in Drug Discovery: A Mini Perspective

In the present work, we have explored the importance of the imidazole ring and its importance in drug discovery, citing the key approvals in the present decade (2013-2024). The pharmacological attribution for the approved drugs revealed that out of 20 approved drugs, 45% of the approvals were made as anti-infectives, followed by approvals under the category of genetic and metabolic disorders, sexual endocrine disorders, anticancer, and to treat blood pressure, gastrointestinal disorders, and neurological conditions. Most approved drugs were dispensed through solid dosage forms (13) and thus had predominantly oral routes beside others. The metabolism pattern revealed that the drugs undergo metabolism via the involvement of multiple enzymes, where CYP3A4 and CYP3A5 were the core enzymes. The excretion pattern of these drugs revealed that the drugs are majorly excreted via the fecal route. The chemical analysis showed that pyrrolidine/pyrrole was the major heterocycle in the approved drugs, followed by the indole ring in the hybridization. Considering the substitution pattern, most drugs possessed amide, amines, and fluoro group as the functional substitution with the 2,4-substitution pattern seen in most approved drugs. Besides this, the three approved drugs were found to possess chiral centers and exhibit chirality. The article also expanded to cover the synthetic routes and metabolic routes for this versatile ring system and case studies for its utility to serve as bioisostere in drug discovery. Furthermore, this article also presents the receptor-ligand interactions of imidazole-based drugs with various target receptors. The present article is, therefore, put forth to assist medicinal chemists and chemists working in drug discovery of this versatile ring system.

Repurposing astemizole to kill multidrug-resistant bacteria isolated in general surgery

Antibiotic resistance has become a significant global public health challenge, particularly in general surgery, where infections caused by resistant bacteria complicate treatment. This study aims to evaluate the potential of the FDA-disapproved antihistamine astemizole as an antibacterial agent, with a focus on its efficacy against methicillin-resistant S. aureus (MRSA). Astemizole demonstrated significant activity against Gram-positive bacteria, especially MRSA, with MIC and MBC values ranging from 4 to 16 μg/mL and 4-32 μg/mL, respectively. However, astemizole showed minimal activity against Gram-negative bacteria. Further investigations revealed that astemizole killed bacteria by disrupting the bacterial membrane, altering membrane potential, inhibiting ATP production, and inducing reactive oxygen species accumulation. Additionally, The resistance mutation frequency of astemizole was low, with only a minor increase in resistance observed in MRSA after 30 days of selective pressure, significantly less than that of ampicillin. Cytotoxicity and hemolysis assays indicated that astemizole was relatively safe at concentrations effective for bacterial inhibition. The Galleria mellonella infection model further confirmed the efficacy of astemizole against MRSA in vivo. Overall, this study provides new insights into the repurposing of astemizole and suggests its potential as a therapeutic agent to address antibiotic resistance.

A comprehensive insight into naphthalimides as novel structural skeleton of multitargeting promising antibiotics

The globally growing antimicrobial resistance seriously threatens human health, increasing efforts have been devoting to the development of novel antibiotics. Naphthalimides contain a special skeleton of cyclic double imides and the naphthalene framework, this unique structure can exert multitargeting abilities which are helpful to overcome the escalating issue of resistance. Therefore, research in connection with the development of naphthalimides as novel antimicrobial agents is becoming progressively active. It has been revealed that naphthalimides as novel structural skeleton of multitargeting promising antibiotics could not only target DNAs and enzymes, disturb membrane, produce reactive oxygen species, etc. suggesting the multitargeting actions which do not induce resistance, but also show a broad antimicrobial spectrum with safety profile and pharmacokinetic characteristics, implying large potential as a new type of antibiotics via continuous efforts toward antimicrobial naphthalimides. This review presents naphthalimides as a new type of potential antimicrobial agents and discusses rational design strategies, structure-activity relationships, and mechanisms of action, with a comprehensive view to providing a new insight for in the rational design of efficient, broad-spectrum, and low-toxic naphthalimide antibiotics.

Facile Synthesis and Applications of Flavonoid-Heterocyclic Derivatives

Flavonoids belong to the polyphenol group that naturally exists in fruits, vegetables, tea, and grains. Flavonoids, as secondary metabolites, show indispensable contributions to biological processes and the responses of plants to numerous environmental factors. The bioactivity of flavonoids depends on C6-C3-C6 ring substitution patterns that exhibit bioactive antioxidant, antimicrobial, antifungal, antitumor, and anti-inflammatory properties. The synthesis of flavonoids has been reported by various methodologies. Therefore, the present review systematically summarizes the synthesis of recent heterocyclic flavonoid derivatives via facile synthetic approaches since the research in flavonoids is useful for therapeutic and biotechnology fields.

An Outline on Benzimidazole Containing Marketed Drugs with Proton Pump Inhibitor and H1 Receptor Antagonist Activities

Heterocyclic compounds are increasingly used in medicinal chemistry because they are the main components of many biological processes and materials. Benzimidazole remains the core center of the heterocyclic chemical group, with essential traits such as six-five-member connected rings and two nitrogen atoms at the 1,3 position in a six-membered benzene and five-membered imidazole- fused ring system. Molecules with benzimidazole derivatives serve important functions as therapeutic agents and have shown excellent results in clinical and biological research. In this comprehensive review, we summarize marketed medications that include the benzimidazole moiety. Here, we discuss two topics: PPIs and H1 receptor antagonists. Benzimidazole derivatives are important in all fields because they have the same isostructural pharmacophore as that of naturally occurring active biomolecules. While PPIs and H1 receptor antagonists are generally safe in the short term, accumulating data suggest that their long-term use may pose concerns. This systematic review aimed to assess global PPI use in the general population. This will help researchers, medicinal chemists, and pharmaceutical scientists to create breakthrough benzimidazole-based drugs. This review can help identify novel lead compounds and optimize existing benzimidazole derivatives to improve medicinal efficacy. Benzimidazole has attracted significant interest because of its high bioavailability, stability, and biological efficiency. This page reveals and discusses typical synthesis processes for marketed pharmaceuticals in the benzimidazole class of scaffolds, MOA, and therapeutic uses.

One-pot, Four-component Synthesis, Molecular Docking and Pharmacokinetic Studies of Tetra-substituted Imidazole Derivatives as Potential Mushroom Tyrosinase Inhibitors

INTRODUCTION

An efficient and four-component one-pot facile synthesis of tetra-substituted imidazole is achieved by cyclo-condensation reaction of benzil with subsequent successive substitution of aromatic aldehydes, ester substituted amine and ammonium acetate via refluxing the mixture for almost two hours at 140°C.

METHODS

The ending point of the understudy reaction was examined by TLC after regular intervals. Synthesized 1,2,4-tetrasubstituted imidazoles were characterized by physical data and the structural features were analyzed using spectroscopic techniques such as FTIR, NMR and elemental analysis.

RESULTS

The inhibition potential of fabricated compounds was evaluated against the mushroom based Tyrosinase (polyphenol oxidase) enzyme. Tetra-substituted imidazole derivatives demonstrated significant potent tyrosinase inhibition activities.

CONCLUSION

Pharmacokinetic mechanism and molecular docking studies were also carried out.

The antibacterial and anti-biofilm effects of novel synthetized nitroimidazole compounds against methicillin-resistant Staphylococcus aureus and carbapenem-resistant Escherichia coli and Klebsiella pneumonia in vitro and in silico

The antibiotic resistance and biofilm formation by bacterial pathogens has led to failure in infections elimination. This study aimed to assess the antibacterial and anti-biofilm properties of novel synthesized nitroimidazole compounds (8a-8o). In this study, nitroimidazole compounds were synthesized via the A3 coupling reaction of sample substrates in the presence of copper-doped silica cuprous sulfate (CDSCS). Fifteen and two carbapenemase producing Escherichia coli and Klebsiella pneumonia (CP-E. coli and CP-K. pneumonia, respectively) and one methicillin-resistant Staphylococcus aureus (MRSA) and one methicillin-susceptible S. aureus (MSSA) plus standard strain of each isolate were included. The antibacterial effects of these compounds demonstrated that the lowest minimum inhibitory and bactericidal concentrations (MIC/MBC, respectively) levels corresponded to compound 8g against S. aureus (1/2 µg/mL) and K. pneumonia (8/32 µg/mL) standard and clinical strains and confirmed by in silico assessment. This was comparable to those of metronidazole being 32-128 µg/mL against K. pneumonia and 32-64 µg/mL against S. aureus. In comparison to metronidazole, against CP-E. coli, compounds 8i and 8m had significantly higher antibacterial effects (p < 0.001) and against CP-K. pneumonia, compounds 8a-8j and 8l-8o had significantly higher (p < 0.0001) antibacterial effects. Compound 8g exhibited significantly higher antibacterial effects against MSSA and compounds 8b (p < 0.001), 8c (p < 0.001), 8d (p < 0.001), 8e (p < 0.001) and 8g (p < 0.0001) exerted significantly higher antibacterial effects than metronidazole against MRSA. Moreover, potential anti-biofilm effects was corresponded to compounds 8a, 8b, 8c, 8e, 8f, 8g, 8i, 8k, 8m and 8n. Considering the antibacterial and anti-biofilm effects of novel synthesized compounds evaluated in this study, further assessments is warranted to verify their properties in vivo and clinical trials in the future.

An insight into recent developments in imidazole based heterocyclic compounds as anticancer agents: Synthesis, SARs, and mechanism of actions

Among all non-communicable diseases, cancer is ranked as the second most common cause of death and is rising constantly. While cancer treatments mainly include radiation therapy, chemotherapy, and surgery; chemotherapy is considered the most commonly employed and effective treatment. Most of the chemotherapeutic agents are azoles based compounds and imidazole is one such insightful azole. The anticancer properties of imidazole-based compounds have been thoroughly explored in recent years and all monosubstituted, disubstituted, trisubstituted, and tetrasubstituted imidazoles have been explored for their anticancer activities. Along with these compounds, other imidazole-based compounds like 1,3-dihydro-2H-imidazole-2-thiones, imidazolones, and poly imidazole compounds have also been explored for their anticancer activities. The activities of these compounds are heavily influenced by their structural resemblance to combretastatin 4A and ABI (2-aryl-4-benzoyl-imidazole). The lead compounds were highly active on breast, gastric, colon, ovarian, cervical, bone marrow, melanoma, prostate, lung, leukemic, neuroblastoma, liver, Ehrlich, melanoma, and pancreatic cancers. The targets of these leads like tubulin, heme oxygenases, VEGF, tyrosine kinases, EGFR, and others have also been explored. The exploration of the anticancer potential of substituted imidazole compounds is the main topic of this review including synthesis, SAR, and mechanism.

Anodic Desulfurization of Heterocyclic Thiones - A Synthesis to Imidazoles and Analogues

An electrochemical desulfurization of 2-mercapto-imidazoles to the corresponding imidazole is established. This novel anodic transformation is bromide-mediated and easy to conduct in the simplest electrochemical setup, consisting of an undivided cell, carbon electrodes, and constant current electrolysis. The method proved successful in 14 diverse examples of imidazoles and triazoles with up to a 97% yield. The scalability was proven in the multigram synthesis of a technically relevant N-heterocyclic carbene (NHC) ligand precursor.

An elegant approach for the synthesis of multisubstituted imidazole via FeCl3/SiO2 catalyzed activation of acetals: a photophysical study of an imidazole-carbazole hybrid

A simple and solvent-free catalytic system was developed for the direct conversion of multisubstituted imidazoles through the reaction of acetals and benzils with ammonium acetate/amines as the source of nitrogen. The reaction occurred under mild and benign conditions using FeCl3/SiO2 as a heterogeneous catalyst without the requirement of any toxic organic solvents. The easy preparation and recyclability of the catalyst allows the reaction to be simple and highly efficient, resulting in very good yields of imidazoles. Novel imidazole-carbazole hybrid compounds were also synthesised by adopting the present methodology. Single crystal X-ray diffraction study indicated the presence of a CH⋯π supramolecular interaction that renders effective molecular packing in the solid state. The steady-state and spectro-dynamic behaviours of these hybrid molecules were investigated, and it was revealed that a solvent-dependent excimer-coupled ICT phenomenon guided excited state photophysics. Very unusual excimer lifetime was noticed in the solid state of this bis-heterocyclic compound owing to the stacking of molecules via CH⋯π interaction, as evident from the X-ray studies.

Imidazoles and Quaternary Ammonium Compounds as Effective Therapies against (Multidrug-Resistant) Bacterial Wound Infections

BACKGROUND/OBJECTIVES

The rise and spread of antimicrobial resistance complicates the treatment of bacterial wound pathogens, further increasing the need for newer, effective therapies. Azoles such as miconazole have shown promise as antibacterial compounds; however, they are currently only used as antifungals. Previous research has shown that combining azoles with quaternary ammonium compounds yields synergistic activity against fungal pathogens, but the effect on bacterial pathogens has not been studied yet.

METHODS

In this study, the focus was on finding active synergistic combinations of imidazoles and quaternary ammonium compounds against (multidrug-resistant) bacterial pathogens through checkerboard assays. Experimental evolution in liquid culture was used to evaluate the possible emergence of resistance against the most active synergistic combination.

RESULTS

Several promising synergistic combinations were identified against an array of Gram-positive pathogens: miconazole/domiphen bromide, ketoconazole/domiphen bromide, clotrimazole/domiphen bromide, fluconazole/domiphen bromide and miconazole/benzalkonium chloride. Especially, miconazole with domiphen bromide exhibits potential, as it has activity at a low concentration against a broad range of pathogens and shows an absence of strong resistance development over 11 cycles of evolution.

CONCLUSIONS

This study provides valuable insight into the possible combinations of imidazoles and quaternary ammonium compounds that could be repurposed for (topical) wound treatment. Miconazole with domiphen bromide shows the highest application potential as a possible future wound therapy. However, further research is needed into the mode of action of these compounds and their efficacy and toxicity in vivo.

Design, synthesis, and biological evaluation of novel imidazole derivatives as analgesic and anti-inflammatory agents: experimental and molecular docking insights

Imidazole moieties exhibit a broad range of biological activities, including analgesic, anti-depressant, anticancer, anti-fungal, anti-tubercular, anti-inflammatory, antimicrobial, antiviral, and antifungal properties. In this study, we explored the use of Schiff base for the synthesis of new imidazole derivatives as anti-inflammatory and pain-relieving agents. A series of eight novel imidazole analogues (2a-h) were prepared in three steps with excellent yields. All compounds were characterized using IR, NMR, and mass spectral data. Their analgesic and anti-inflammatory activities were evaluated using hot plate and paw oedema methods. Compound 2 g (1-(2,3-dichlorophenyl)-2-(3-nitrophenyl)-4,5-diphenyl-1H-imidazole) showed significant analgesic activity (89% at 100 mg/kg b.w.), while compounds 2a (2-(2,6-dichlorophenyl)-1-(4-ethoxyphenyl)-4,5-diphenyl-1H-imidazole) and 2b (2-(2,3-dichlorophenyl)-1-(2-chlorophenyl)-4,5-diphenyl-1H-imidazole) exhibited good anti-inflammatory activity (100% at 100 mg/kg b.w.), comparable to diclofenac salt (100% at 50 mg/kg b.w.). Molecular docking studies were conducted using Schrödinger software version 2021-2, employing the OPLS4 force field for both receptor and ligand preparation. The results were visualized using molecular visualization software such as PyMOL. These studies revealed that compound 2g exhibited the highest binding affinity with the COX-2 receptor (-5.516 kcal/mol). Compound 2g formed three conventional hydrogen bonds with residues GLN-242 (bond length: 2.3 Å) and ARG-343 (bond lengths: 2.2 Å & 2.4 Å). This binding affinity was comparable to that of Diclofenac salt, which showed the highest binding affinity of -5.627 kcal/mol with the COX-2 receptor. Diclofenac salt formed two conventional hydrogen bonds with the residues ARG-344 (bond length: 2.0 Å) and TRP-140 (bond length: 1.7 Å). Later, molecular dynamic simulations confirmed the stable binding affinity of compound 2g with the protein. Furthermore, other compounds also demonstrated potential binding to the receptor-binding pocket region. The anti-inflammatory potential of the synthesized compounds was evaluated using the carrageenan-induced rat hind paw oedema model, while the analgesic potential was assessed using the hot plate method. These evaluations were conducted in comparison with Diclofenac sodium, serving as the standard compound. However, compound 2g stood out for its superior analgesic activity, as confirmed by in-vivo examination. These findings suggest that these novel imidazole derivatives have potential as anti-inflammatory and analgesic agents.

Imidazole Compounds: Synthesis, Characterization and Application in Optical Analysis

Imidazole is a five-membered heterocyclic ring containing three carbon atoms, two nitrogen atoms, and two double bonds. Among two nitrogen atoms, one of which carries with a hydrogen atom is a pyrrole-type nitrogen atom, another is a pyridine type nitrogen atom. Hence, the imidazole ring belongs to the π electron-rich aromatic ring and can accept strong suction to the electronic group. Moreover, the nitrogen atom of the imidazole ring is coordinated with metal ions to form metal-organic frameworks. In recent years, because of imidazole compounds' unique optical properties, their applications have attracted more and more attention in optical analysis. Thus, this review has summarized the synthesis, characterization, and application with emphasis on the research progress of imidazole compounds in optical analysis, including fluorescence probe, colorimetric probe, electrochemiluminescence sensor, fiber optical sensor, surface plasmon resonance, etc. This paper will suggest the direction for the development of imidazole-containing sensors with high sensitivity and selectivity.

Synthesis and characterization of 2-(anthracene-9-yl)-4,5-diphenyl-1H-imidazole derivatives as environmentally sensitive fluorophores

2-(Anthracene-9-yl)-4,5-diphenyl-1H-imidazole (ADPI) provides an intriguing molecular platform for developing organic fluorophores with diverse properties and fluorescence performances. However, derivatives of ADPI have not yet been well explored and extensive studies are warranted. To shed more light on this, we have synthesized a series of π-extended ADPIs through a concise synthetic route involving an efficient cross-condensation reaction followed by Pd-catalyzed Suzuki cross-coupling. The obtained compounds were subjected to X-ray single crystallographic analysis to understand their molecular conformational and solid-state packing properties. Furthermore, UV-Vis absorption and fluorescence spectroscopic analyses were conducted. Our experimental results have disclosed interesting solvatofluorochromic properties of these compounds which are useful for solvent polarity-sensitive applications. The presence of an amphoteric imidazolyl group in the ADPI derivatives also renders them sensitive fluorescence responses to strong protic acids (e.g., trifluoroacetic acid) as well as fluoride anion. It transpires that the fluorescence changes are dependent on the functional groups attached to the ADPI core, suggesting a bottom-up molecular tuning approach for development of fluorophores and chemosensors with diverse functions.

Cyclocondensation of 2-(α-Diazoacyl)-2H-azirines with Amidines in Diazo Synthesis of Functionalized Naphtho[1,2-d]imidazoles

A diazo approach toward functionalized naphtho[1,2-d]imidazole derivatives has been developed. It involved a new reaction of arylamidines with 2-(α-diazoacyl)-2H-azirines giving 5-aryl-4-(α-diazoacyl)-1H-imidazoles under mild conditions in good yields. The mechanism of annulation of azirines with amidines is discussed based on DFT calculations. The reaction proceeds in an unusual manner by cleavage of the azirine C-C bond, allowing for the transfer of the aryl substituent from the arylamidine to the proper position of the key intermediate of naphtho[1,2-d]imidazole synthesis. Under thermolysis conditions, 5-aryl-4-(α-diazoacyl)-1H-imidazoles undergo Wolff rearrangement followed by the selective 6π-cyclization of transient ketene to form 3H-naphtho[1,2-d]imidazoles bearing various substituents in the positions 2,3,4,5,7,8,9. Additionally, variation of the substituents at position 5 of naphtho[1,2-d]imidazoles is possible through the formation of triflates and subsequent cross-coupling reactions. One more heterocyclic pharmacophoric skeleton, 3H-furo[3',2':3,4]naphtho[1,2-d]imidazole, was easily constructed from methyl 5-hydroxy-3H-naphtho[1,2-d]imidazole-4-carboxylates in a one-pot mode using O-alkylation with phenacyl bromides followed by base-induced intramolecular acyl substitution at room temperature with high yields.

The Cohesive Interactions in Phenylimidazoles

This work presents a comprehensive study exploring the thermodynamics of the solid phase of a series of phenylimidazoles, encompassing experimental measurements of heat capacity, volatility, and thermal behavior. The influence of successive phenyl group insertions on the imidazole ring on thermodynamic properties and supramolecular behavior was thoroughly examined through the evaluation of 2-phenylimidazole (2-PhI), 4-phenylimidazole (4-PhI), 4,5-diphenylimidazole (4,5-DPhI), and 2,4,5-triphenylimidazole (2,4,5-TPhI). Structural correlations between molecular structure and thermodynamic properties were established. Furthermore, the investigation employed UV-vis spectroscopy and quantum chemical calculations. Additive effects arising from the introduction of phenyl groups were found through the analysis of the solid-liquid and solid-gas equilibria, as well as heat capacities. A good correlation emerged between the thermodynamic properties of sublimation and the molar volume of the unit cell, evident across 2-PhI, 4,5-DPhI, and 2,4,5-TPhI. In contrast to its isomer 2-PhI, 4-PhI exhibited greater cohesive energy due to the stronger N-H···N intermolecular interactions, leading to the disruption of coplanar geometry in the 4-PhI molecules. The observed higher entropies of phase transition (fusion and sublimation) are consistent with the higher structural order observed in the crystalline lattice of 4-PhI.

Synthesis, Characterization, Molecular Docking, and Investigation of Antibacterial Properties of New Derivatives of 1-H-Phenanthro [9,10-d] Imidazole

In this study, several imidazole derivatives in one pot multicomponent reaction from various aldehydes 1(a-z), 9,10-phenanthrenequinone, or benzyl (2), and ammonium acetate (3) were synthesized in the presence of acetic acid (AcOH) under reflux conditions at 120 °C. Also, the photochromic properties of synthesized compounds were investigated in AcOH as a solvent under laboratory conditions at a temperature of 120 °C. Moreover, the antibacterial activity of the synthesized compounds was investigated. The structure of the products was confirmed using FT-IR, UV-Vis, 1H-NMR, and 13CNMR spectroscopy. The antimicrobial activity of these compounds against gram-positive bacteria including Bacillus subtilis (B. subtilis) and gram-negative bacteria including Escherichia coli (E.coli) bacteria was evaluated by the Well diffusion (WD) method, and the compounds 4 o showed significant results for both antibacterial activity. To gain insight into how these compounds interact with two types of targets, i. e., human topoisomerase II alpha (5GWK) and acetylcholinesterase (7AIX), binding calculations have been used that provide significant results for both targets and show that most ligands can effectively bind to cleft nucleotides. Interfere in the first one or be well placed in them. Hydrophobic pocket in the dimension, which can ultimately lead to high scores achieved.

Three-component cascade reaction of 3-ketonitriles, 2-unsubstituted imidazole N-oxides, and aldehydes

A three-component condensation of 2-unsubstituted imidazole N-oxides, 3-ketonitriles, and aldehydes is described. The reaction proceeds via sequential Knoevenagel condensation/Michael addition under mild, catalyst-free conditions with various substrates. Furthermore, the corresponding 2-functionalized imidazole N-oxides can be further dehydrated to (Z)-2-aroyl-3-(1H-imidazol-2-yl)-acrylonitriles, which may also be directly prepared by changing the reaction conditions as a cascade of Knoevenagel condensation/Michael addition/dehydration.

Mutual influence of non-covalent interactions formed by imidazole: A systematic quantum-chemical study

Imidazole is a five-membered heterocycle that is part of a number of biologically important molecules such as the amino acid histidine and the hormone histamine. Imidazole has a unique ability to participate in a variety of non-covalent interactions involving the NH group, the pyridine-like nitrogen atom or the π-system. For many biologically active compounds containing the imidazole moiety, its participation in formation of hydrogen bond NH⋯O/N and following proton transfer is the key step of mechanism of their action. In this work a systematic study of the mutual influence of various paired combinations of non-covalent interactions (e.g., hydrogen bonds and π-interactions) involving the imidazole moiety was performed by means of quantum chemistry (PW6B95-GD3/def2-QZVPD) for a series of model systems constructed based on analysis of available x-ray data. It is shown that for considered complexes formation of additional non-covalent interactions can only enhance the proton-donating ability of imidazole. At the same time, its proton-accepting ability can be both enhanced and weakened, depending on what additional interactions are added to a given system. The mutual influence of non-covalent interactions involving imidazole can be classified as weak geometric and strong energetic cooperativity-a small change in the length of non-covalent interaction formed by imidazole can strongly influence its strength. The latter can be used to develop methods for controlling the rate and selectivity of chemical reactions involving the imidazole fragment in larger systems. It is shown that the strong mutual influence of non-covalent interactions involving imidazole is due to the unique ability of the imidazole ring to effectively redistribute electron density in non-covalently bound systems with its participation.

Dual COX-2 and 15-LOX inhibition study of novel 4-arylidine-2-mercapto-1-phenyl-1H-imidazolidin-5(4H)-ones: Design, synthesis, docking, and anti-inflammatory activity

Novel arylidene-5(4H)-imidazolone derivatives 4a-r were designed and evaluated as multidrug-directed ligands, that is, inflammatory, proinflammatory mediators, and reactive oxygen species (ROS) inhibitors. All of the tested compounds showed cyclooxygenase (COX)-1 inhibitory effect more than celecoxib and less than indomethacin and also demonstrated an improved inhibitory activity against 15-lipoxygenase (15-LOX). Compounds 4f, 4l, and 4p exhibited COX-2 selectivity comparable to that of celecoxib, while 4k was the most selective COX-2 inhibitor. Interestingly, the screened results showed that compound 4k exhibited a superior inhibition effect against 15-LOX and was found to be the most selective COX-2 inhibitor over celecoxib, whereas compound 4f showed promising COX-2 and 15-LOX inhibitory activities besides its inhibitory effect against ROS production and its lowering effect of both tumor necrosis factor-α and interleukin-6 levels by ∼80%. Moreover, compound 4f attenuated the lipopolysaccharide-mediated increase in NF-κB activation in RAW 264.7 macrophages. The preferred binding affinity of these molecules was confirmed by docking studies. We conclude that arylidene-5(4H)-imidazolone scaffolds provide promising hits for developing new synthons with anti-inflammatory and antioxidant activities.

Time-series analysis of rhenium(I) organometallic covalent binding to a model protein for drug development

Metal-based complexes with their unique chemical properties, including multiple oxidation states, radio-nuclear capabilities and various coordination geometries yield value as potential pharmaceuticals. Understanding the interactions between metals and biological systems will prove key for site-specific coordination of new metal-based lead compounds. This study merges the concepts of target coordination with fragment-based drug methodologies, supported by varying the anomalous scattering of rhenium along with infrared spectroscopy, and has identified rhenium metal sites bound covalently with two amino acid types within the model protein. A time-based series of lysozyme-rhenium-imidazole (HEWL-Re-Imi) crystals was analysed systematically over a span of 38 weeks. The main rhenium covalent coordination is observed at His15, Asp101 and Asp119. Weak (i.e. noncovalent) interactions are observed at other aspartic, asparagine, proline, tyrosine and tryptophan side chains. Detailed bond distance comparisons, including precision estimates, are reported, utilizing the diffraction precision index supplemented with small-molecule data from the Cambridge Structural Database. Key findings include changes in the protein structure induced at the rhenium metal binding site, not observed in similar metal-free structures. The binding sites are typically found along the solvent-channel-accessible protein surface. The three primary covalent metal binding sites are consistent throughout the time series, whereas binding to neighbouring amino acid residues changes through the time series. Co-crystallization was used, consistently yielding crystals four days after setup. After crystal formation, soaking of the compound into the crystal over 38 weeks is continued and explains these structural adjustments. It is the covalent bond stability at the three sites, their proximity to the solvent channel and the movement of residues to accommodate the metal that are important, and may prove useful for future radiopharmaceutical development including target modification.

Unlocking InhA: Novel approaches to inhibit Mycobacterium tuberculosis

Multidrug-resistant tuberculosis continues to pose a health security risk and remains a public health emergency. Antimicrobial resistance result from treatment regimens that are both insufficient and incomplete leading to the emergence of multidrug-resistant tuberculosis, extensively drug-resistant tuberculosis and totally drug-resistant tuberculosis. The impact of tuberculosis on the people suffering from HIV (Human immunodeficiency virus infection) have resulted in the increased research efforts in designing and discovery of novel antitubercular drugs that may result in decreasing treatment duration, minimising the need for multiple drug intake, minimising cytotoxicity and enhancing the mechanism of action of drug. While many drugs are available to treat tuberculosis, a precise and timely cure is still absent. Consequently, further investigation is needed to identify more recent molecular equivalents that have the potential to swiftly remove this disease. Isoniazid (INH), a treatment for tuberculosis (TB), targets the enzyme InhA (mycobacterium enoyl acyl carrier protein reductase), the Mycobacterium tuberculosis enoyl-acyl carrier protein (ACP) reductase, most common INH resistance is circumvented by InhA inhibitors that do not require KatG (catalase-peroxidase) activation, as a result, researchers are trying to work in the area of development of InhA inhibitors which could help in eradicating the era of tuberculosis from the world.

Thiazolotriazoles As Anti-infectives: Design, Synthesis, Biological Evaluation and In Silico Studies

The rational design of novel thiazolo[2,3-c][1,2,4]triazole derivatives was carried out based on previously identified antitubercular hit molecule H127 for discovering potent compounds showing antimicrobial activity. The designed compounds were screened for their binding efficacies against the antibacterial drug target enoyl-[acyl-carrier-protein] reductase, followed by prediction of drug-likeness and ADME properties. The designed analogues were chemically synthesized, characterized by spectroscopic techniques, followed by evaluation of antimicrobial activity against bacterial and fungal strains, as well as antitubercular activity against M. tuberculosis and M. bovis strains. Among the synthesized compounds, five compounds, 10, 11, 35, 37 and 38, revealed antimicrobial activity, albeit with differential potency against various microbial strains. Compounds 10 and 37 were the most active against S. mutans (MIC: 8 μg/mL), while compounds 11 and 37 showed the highest activity against B. subtillis (MIC: 16 μg/mL), whereas compounds 10, 11 and 37 displayed activities against E. coli (MIC: 16 μg/mL). Meanwhile, compounds 10 and 35 depicted activities against S. typhi (MIC: 16 μg/mL) and compound 10 showed antifungal activity against C. albicans (MIC: 32 μg/mL). The current study has identified two broad-spectrum antibacterial hit compounds (10 and 37). Further structural investigation on these molecules is underway to enhance their potency.

Novel azole-sulfonamide conjugates as potential antimicrobial candidates: synthesis and biological assessment

Background: Azole and sulfonamide molecular frameworks are endowed with potent antimicrobial activity. Materials & methods: A series of azole-sulfonamide conjugates were synthesized using click reaction of N-propargylated imidazole with azide of sulfonamide and its antimicrobial efficacy was evaluated. Results: The compounds 7c, 7i and 7r displayed promising antibacterial activities, better than the standards sulfonamide and norfloxacin. All molecules exhibited promising antifungal activity, more potent than fluconazole. Docking studies of the active conjugates signified the importance of hydrophobic interactions in hosting the molecules in the active site of dihydrofolate reductase. Conclusion: Azole-sulfonamide conjugates are more active than single sulfonamide moieties and 7c, 7i and 7r may prove valuable leads for further optimization as novel antimicrobial agents.

Isolation by multistep chromatography improves the consistency of secreted recombinant influenza neuraminidase antigens

Recombinant protein-based approaches are ideally suited for producing vaccine antigens that are not overly abundant in viruses, such as influenza neuraminidase (NA). However, obtaining sufficient quantities of recombinant viral surface antigens remains challenging, often resulting in the use of chimeric proteins with affinity tags that can invariably impact the antigen's properties. Here, we developed multistep chromatography approaches for purifying secreted recombinant NA (rNA) antigens that are derived from recent H1N1 and H3N2 viruses and produced using insect cells. Analytical analyses showed that these isolation procedures yielded homogenous tetrameric rNA preparations with consistent specific activities that were not possible from a common immobilized metal affinity chromatography purification procedure. The use of classical chromatography improved the rNA tetramer homogeneity by removing the requirement of the N-terminal poly-histidine affinity tag that was shown to promote higher order rNA oligomer formation. In addition, these procedures reduced the specific activity variation by eliminating the exposure to Ni2+ ions and imidazole, with the latter showing pH and NA subtype dependent effects. Together, these results demonstrate that purification by multistep chromatography improves the homogeneity of secreted rNAs and eliminates the need for affinity tag-based approaches that can potentially alter the properties of these recombinant antigens.

Approaches Towards Better Immunosuppressive Agents

Several classes of compounds are applied in clinics due to their immunosuppressive properties in transplantology and the treatment of autoimmune diseases. Derivatives of mycophenolic acid, corticosteroids and chemotherapeutics bearing heterocyclic moieties like methotrexate, azathioprine, mizoribine, and ruxolitinib are active substances with investigated mechanisms of action. However, improved synthetic approaches of known drugs and novel derivatives are still being reported to attempt better accessibility and therapeutic properties. In this review article, we present the synthesis of the designed chemical structures based on recent literature reports concerning novel compounds as promising immunosuppressive drugs. Moreover, some of the discussed derivers revealed also other types of activities with prospective medicinal potential.

In Silico, in Vitro and in Vivo Study of Substituted Imidazolidinone Sulfonamides as Antibacterial Agents

New substituted imidazolidinone sulfonamides have been developed using a rational drug design strategy. Predictive QSAR models for the search of new antibacterials were created using the OCHEM platform. Regression models were applied to verify a virtual chemical library of new imidazolidinone derivatives designed to have antibacterial activity. A number of substituted imidazolidinone sulfonamides as effective antibacterial agents were identified by QSAR prediction, synthesized and characterized by spectral and elemental, and tested in vitro. Six studied compounds have shown the highest in vitro antibacterial activity against Gram-negative E. coli and Gram-positive S. aureus multidrug-resistant strains. The in vivo acute toxicity of these imidazolidinone sulfonamides based on the LC50 value ranged from 16.01 to 44.35 mg/L (slightly toxic compounds class). The results of molecular docking suggest that the antibacterial mechanism of the compounds can be associated with the inhibition of post-translational modification processes of bacterial peptides and proteins.

Particleboards Bonded by an Imidazole-Based Adhesive System

Particleboards with different combinations of the adhesive material imidazole, citric acid, and sorbitol were produced. Softwood sawdust from a Swedish sawmill was mixed with an aqueous solution of the chemicals and then dried to 0% moisture content prior to pressing. The boards were pressed to a target density of 700 kg m-3 at either 200 °C or 220 °C for 10 min. The hygroscopic and mechanical properties of the boards were clearly better at 220 °C than 200 °C for all used chemical combinations. A combination of imidazole (14.4 wt%) and citric acid (11.3 wt%) led to the best results, where the thickness swelling after 24 h of water immersion was 6.3% and the internal bonding strength was 0.57 MPa. The modulus of rupture and modulus of elasticity were 3.3 MPa and 1.1 GPa, respectively. Cyclic accelerated weathering showed exceptional stability with a thickness change after boiling and drying of only 2.1% compared to the initial dry thickness. This study indicates that the presence of imidazole leads to greatly improved hygroscopic properties and good internal bonding strength when used in particleboards.

Design, Synthesis, and Anti-Breast Cancer Potential of Imidazole-Pyridine Hybrid Molecules In Vitro and Ehrlich Ascites Carcinoma Growth Inhibitory Activity Assessment In Vivo

Breast cancer remains a challenging medical issue and is a high priority for biomedical research despite significant advancements in cancer research and therapy. The current study aims to determine the anticancer activity of a group of imidazole-pyridine-based scaffolds against a variety of breast cancer cell lines differing in their receptor expression (estrogen receptor (ER), progesterone receptor (PR), and HER-2). A series of 10 molecules (coded 5a-5j) were synthesized through multicomponent and alkylation reactions. FTIR, MS, 1H, and 13C NMR spectral analyses confirmed the structures and purity of the synthesized molecules. Subsequently, these molecules were tested for their ability to inhibit the viability of cell lines representing carcinoma of the breast, viz., MDA-MB-468 (ER-, PR-, and HER-), BT-474 (ER+, PR+, and HER+), T-47D (ER+, PR+, and HER-), and MCF-7 (ER+, PR+, and HER-) in vitro. Among these 10 molecules, 5a, 5c, 5d, and 5e exhibited better potency, as evidenced by IC50 < 50 μM at 24 h of treatment against BT-474 and MDA-MB-468 cell lines. However, except for 5d, the IC50 value is much higher than 50 μM when tested against T47D and MCF-7 cell lines at 24h. Extended treatment for 48 h reduced the effect of these molecules, as an increase in IC50 was observed. In mice, intraperitoneal administration of 5e retarded the Ehrlich ascites carcinoma (EAC) growth without causing any organ toxicity at the doses tested. In summary, we report the synthesis scheme and key structural requirements for a new series of imidazole-pyridine molecules for in vitro inhibition of the feasibility of breast cancer cells and in vivo inhibition of EAC tumors.

The Role of Five-Membered Heterocycles in the Molecular Structure of Antibacterial Drugs Used in Therapy

Five-membered heterocycles are essential structural components in various antibacterial drugs; the physicochemical properties of a five-membered heterocycle can play a crucial role in determining the biological activity of an antibacterial drug. These properties can affect the drug's activity spectrum, potency, and pharmacokinetic and toxicological properties. Using scientific databases, we identified and discussed the antibacterials used in therapy, containing five-membered heterocycles in their molecular structure. The identified five-membered heterocycles used in antibacterial design contain one to four heteroatoms (nitrogen, oxygen, and sulfur). Antibacterials containing five-membered heterocycles were discussed, highlighting the biological properties imprinted by the targeted heterocycle. In some antibacterials, heterocycles with five atoms are pharmacophores responsible for their specific antibacterial activity. As pharmacophores, these heterocycles help design new medicinal molecules, improving their potency and selectivity and comprehending the structure-activity relationship of antibiotics. Unfortunately, particular heterocycles can also affect the drug's potential toxicity. The review extensively presents the most successful five-atom heterocycles used to design antibacterial essential medicines. Understanding and optimizing the intrinsic characteristics of a five-membered heterocycle can help the development of antibacterial drugs with improved activity, pharmacokinetic profile, and safety.

Enteric-coating film effect on the delayed drug release of pantoprazole gastro-resistant generic tablets

Background: Enteric coating films in acidic labile tablets protect the drug molecule from the acidic environment of the stomach. However, variations in the excipients used in the coating formulation may affect their ability to provide adequate protection. This study is the first to investigate the potential effects of coating materials on the protective functionality of enteric coating films for pantoprazole (PNZ) generic tablets after their recall from the market. Methods: A comparative analysis was conducted between generic and branded PNZ products, using pure drug powder for identification. The in vitro release of the drug was evaluated in different pH media. The study also utilized various analytical and thermal techniques, including differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), and confocal Raman microscopy. Results: The in vitro assessment results revealed significant variations in the release profile for the generic product in acidic media at 120 min. DSC and TGA thermal profile analyses showed slight variation between the two products. XRD analysis exhibited a noticeable difference in peak intensity for the generic sample, while SEM revealed smaller particle sizes in the generic product. The obtained spectra profile for the generic product displayed significant variation in peaks and band intensity, possibly due to impurities. These findings suggest that the excipients used in the enteric coating film of the generic product may have affected its protective functionality, leading to premature drug release in acidic media. Additionally, the presence of polysorbate 80 (P-80) in the brand product might improve the properties of the enteric coating film due to its multi-functionality. Conclusions: In conclusion, the excipients used in the brand product demonstrated superior functionality in effectively protecting the drug molecule from acidic media through the enteric coating film, as compared to the generic version.

Identification of a New Compound (4-Fluoro-2-Trifluoromethyl Imidazole) Extracted from a New Halophilic Bacillus aquimaris Strain Persiangulf TA2 Isolated from the Northern Persian Gulf with Broad-Spectrum Antimicrobial Effect

Background

The unique ecosystem of the Persian Gulf has made it a rich source of natural antimicrobial compounds produced by various microorganisms, especially bacteria, which can be used in the treatment of infectious diseases, especially those of drug-resistant microbes.

Objectives

This study aimed to identify antimicrobial compounds in the bacteria isolated from the northern region of the Persian Gulf in Abadan (Chavibdeh port), Iran, for the first time.

Materials and Methods

Sampling was performed in the fall on November 15, 2019, from 10 different stations (water and sediment samples). The secondary metabolites of all isolates were extracted, and their antimicrobial effects were investigated. 16S ribosomal ribonucleic acid sequencing was used for the identification of the strains that showed the best inhibition against selected pathogens, and growth conditions were optimized for them. A fermentation medium in a volume of 5000 mL was prepared to produce the antimicrobial compound by the superior strain. The extracted antimicrobial compounds were identified using the gas chromatography-mass spectrometry technique. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for the superior strain. The effects of salinity, pH, and temperature on the production of antimicrobial compounds were determined by measuring the inhibitory region (mm) of methicillin-resistant Staphylococcus aureus (MRSA).

Results

Four new strains with antimicrobial properties (i.e., Halomonas sp. strain Persiangulf TA1, Bacillus aquimaris strain Persiangulf TA2, Salinicoccus roseus strain Persiangulf TA4, and Exiguobacterium profundum strain Persiangulf TA9) were identified. The optimum growth temperatures were determined at 37-30, 37, and 40 °C for TA1 and TA2, TA4, and TA9 strains, respectively. The optimum pH values for the four strains were 7, 6-7, 7.5, and 6.5-7.5, respectively. The optimal salt concentrations for the four strains were 15%, 2.5-5%, 7.5%, and 5%, respectively. The ethyl acetate extract of strain Persiangulf TA2 showed extensive antimicrobial activity against human pathogens (75%) and MRSA. The most abundant compound identified in TA2 extract was the new compound 4-fluoro-2-trifluoromethyl imidazole. The MBC and MIC for the ethyl acetate extract of strain TA2 were 20 and 5 mg. mL-1 (Staphylococcus aureus), 40 and 20 mg. mL-1 (MRSA, Escherichia coli, and Enterococcus faecalis), 40 and 10 mg. mL-1 Acinetobacter baumannii), and 80 and 40 mg. mL-1 (Staphylococcus epidermidis, Shigella sp., Bacillus cereus, and Klebsiella pneumoniae), respectively. The optimal conditions for antibiotic production by TA2 strain were 5% salt concentration, pH of 7, and temperature of 35 °C.

Conclusion

Newly detected natural compounds in TA2 strain due to superior antimicrobial activity even against MRSA strain can be clinically valuable in pharmacy and treatment.

Imidazoles as Serotonin Receptor Modulators for Treatment of Depression: Structural Insights and Structure-Activity Relationship Studies

Serotoninergic signaling is identified as a crucial player in psychiatric disorders (notably depression), presenting it as a significant therapeutic target for treating such conditions. Inhibitors of serotoninergic signaling (especially selective serotonin reuptake inhibitors (SSRI) or serotonin and norepinephrine reuptake inhibitors (SNRI)) are prominently selected as first-line therapy for the treatment of depression, which benefits via increasing low serotonin levels and norepinephrine by blocking serotonin/norepinephrine reuptake and thereby increasing activity. While developing newer heterocyclic scaffolds to target/modulate the serotonergic systems, imidazole-bearing pharmacophores have emerged. The imidazole-derived pharmacophore already demonstrated unique structural characteristics and an electron-rich environment, ultimately resulting in a diverse range of bioactivities. Therefore, the current manuscript discloses such a specific modification and structural activity relationship (SAR) of attempted derivatization in terms of the serotonergic efficacy of the resultant inhibitor. We also featured a landscape of imidazole-based development, focusing on SAR studies against the serotoninergic system to target depression. This study covers the recent advancements in synthetic methodologies for imidazole derivatives and the development of new molecules having antidepressant activity via modulating serotonergic systems, along with their SAR studies. The focus of the study is to provide structural insights into imidazole-based derivatives as serotonergic system modulators for the treatment of depression.

Different Structures-Similar Effect: Do Substituted 5-(4-Methoxyphenyl)-1H-indoles and 5-(4-Methoxyphenyl)-1H-imidazoles Represent a Common Pharmacophore for Substrate Selective Inhibition of Linoleate Oxygenase Activity of ALOX15?

Mammalian 15-lipoxygenases (ALOX15) are lipid peroxidizing enzymes that exhibit variable functionality in different cancer and inflammation models. The pathophysiological role of linoleic acid- and arachidonic acid-derived ALOX15 metabolites rendered this enzyme a target for pharmacological research. Several indole and imidazole derivatives inhibit the catalytic activity of rabbit ALOX15 in a substrate-specific manner, but the molecular basis for this allosteric inhibition remains unclear. Here, we attempt to define a common pharmacophore, which is critical for this allosteric inhibition. We found that substituted imidazoles induce weaker inhibitory effects when compared with the indole derivatives. In silico docking studies and molecular dynamics simulations using a dimeric allosteric enzyme model, in which the inhibitor occupies the substrate-binding pocket of one monomer, whereas the substrate fatty acid is bound at the catalytic center of another monomer within the ALOX15 dimer, indicated that chemical modification of the core pharmacophore alters the enzyme-inhibitor interactions, inducing a reduced inhibitory potency. In our dimeric ALOX15 model, the structural differences induced by inhibitor binding are translated to the hydrophobic dimerization cluster and affect the structures of enzyme-substrate complexes. These data are of particular importance since substrate-specific inhibition may contribute to elucidation of the putative roles of ALOX15 metabolites derived from different polyunsaturated fatty acids in mammalian pathophysiology.

Synthesis, Structure and Biological Activity of Indole-Imidazole Complexes with ZnCl2: Can Coordination Enhance the Functionality of Bioactive Ligands?

The ability of the indole-imidazole hybrid ligands to coordinate with the Zn(II) ion and the resulting structures of this new class of coordination compounds were analyzed in order to determine their structural properties and biological functionalities. For this purpose, six novel Zn(II) complexes, [Zn(InIm)₂Cl₂] (1), [Zn(InMeIm)₂Cl₂] (2), [Zn(IniPrIm)₂Cl₂] (3), [Zn(InEtMeIm)₂Cl₂] (4), [Zn(InPhIm)₂Cl₂] (5) and [Zn₂(InBzIm)₂Cl₂] (6) (where InIm is 3-((1H-imidazol-1-yl)methyl)-1H-indole), were synthesized by the reactions of ZnCl₂ and the corresponding ligand in a 1:2 molar ratio in methanol solvent at an ambient temperature. The structural and spectral characterization of these complexes was performed using NMR, FT-IR and ESI-MS spectrometry and elemental analysis, and the crystal structures of 1-5 were determined using single-crystal X-ray diffraction. Complexes 1-5 form polar supramolecular aggregates by utilizing, for this purpose, the N-H(indole)∙∙∙Cl(chloride) intermolecular hydrogen bonds. The assemblies thus formed differ depending on the distinctive molecular shape, which can be either compact or extended. All complexes were screened for their hemolytic, cytoprotective, antifungal, and antibacterial activities. The results show that the cytoprotective activity of the indole/imidazole ligand significantly increases upon its complexation with ZnCl₂ up to a value comparable with the standard antioxidant Trolox, while the response of its substituted analogues is diverse and less pronounced.

New polyimidazole ligands against subclass B1 metallo-β-lactamases: Kinetic, microbiological, docking analysis

Beta-lactam antibiotics are one of the most commonly used drug classes in managing bacterial infections. However, their use is threatened by the alarming phenomenon of antimicrobial resistance, which represents a worldwide health concern. Given the continuous spread of metallo-β-lactamases (MBLs) producing pathogens, the need to discover broad-spectrum β-lactamase inhibitors is increasingly growing. A series of zinc chelators have been synthesized and investigated for their ability to hamper the Zn-ion network of interactions in the active site of MBLs. We assessed the inhibitory activity of new polyimidazole ligands N,N'-bis((imidazol-4-yl)methyl)-ethylenediamine, N,N,N'-tris((imidazol-4-yl)methyl)-ethylenediamine, N,N,N,N'-tetra((imidazol-4-yl-methyl)-ethylenediamine toward three different subclasses B1 MBLs: VIM-1, NDM-1 and IMP-1 by in vitro assays. The activity of known zinc chelators such as 1,4,7,10,13-Pentaazacyclopentadecane, 1,4,8,11-Tetraazacyclotetradecane and 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid was also assessed. Moreover, a molecular docking study was carried to gain insight into the interaction mode of the most active ligands.

Comprehensive Insights into Medicinal Research on Imidazole-Based Supramolecular Complexes

The electron-rich five-membered aromatic aza-heterocyclic imidazole, which contains two nitrogen atoms, is an important functional fragment widely present in a large number of biomolecules and medicinal drugs; its unique structure is beneficial to easily bind with various inorganic or organic ions and molecules through noncovalent interactions to form a variety of supramolecular complexes with broad medicinal potential, which is being paid an increasing amount of attention regarding more and more contributions to imidazole-based supramolecular complexes for possible medicinal application. This work gives systematical and comprehensive insights into medicinal research on imidazole-based supramolecular complexes, including anticancer, antibacterial, antifungal, antiparasitic, antidiabetic, antihypertensive, and anti-inflammatory aspects as well as ion receptors, imaging agents, and pathologic probes. The new trend of the foreseeable research in the near future toward imidazole-based supramolecular medicinal chemistry is also prospected. It is hoped that this work provides beneficial help for the rational design of imidazole-based drug molecules and supramolecular medicinal agents and more effective diagnostic agents and pathological probes.

N-, O- and S-Heterocycles Synthesis in Deep Eutectic Solvents

The synthesis of heterocycles is a fundamental area of organic chemistry that offers enormous potential for the discovery of new products with important applications in our daily life such as pharmaceuticals, agrochemicals, flavors, dyes, and, more generally, engineered materials with innovative properties. As heterocyclic compounds find application across multiple industries and are prepared in very large quantities, the development of sustainable approaches for their synthesis has become a crucial objective for contemporary green chemistry committed to reducing the environmental impact of chemical processes. In this context, the present review focuses on the recent methodologies aimed at preparing N-, O- and S-heterocyclic compounds in Deep Eutectic Solvents, a new class of ionic solvents that are non-volatile, non-toxic, easy to prepare, easy to recycle, and can be obtained from renewable sources. Emphasis has been placed on those processes that prioritize the recycling of catalyst and solvent, as they offer the dual benefit of promoting synthetic efficiency while demonstrating environmental responsibility.

Simple Synthetic Approach to N-(Pyridin-2-yl)imidates from Nitrostyrenes and 2-Aminopyridines via the N-(Pyridin-2-yl)iminonitriles as Intermediates

A facile, green, synthetic protocol of several substituted N-(pyridin-2-yl)imidates from nitrostyrenes and 2-aminopyridines via the corresponding N-(pyridin-2-yl)iminonitriles as intermediates is reported. The reaction process involved the in situ formation of the corresponding α-iminontriles under heterogeneous Lewis acid catalysis in the presence of Al₂O₃. Subsequently, α-iminonitriles were selectively transformed into the desired N-(pyridin-2-yl)imidates under ambient conditions and in the presence of Cs₂CO₃ in alcoholic media. Under these conditions, 1,2- and 1,3-propanediols also led to the corresponding mono-substituted imidates at room temperature. The present synthetic protocol was also developed on one mmol scale, providing access to this important scaffold. A preliminary synthetic application of the present N-(pyridin-2-yl)imidates was carried out for their facile conversion into the N-heterocycles 2-(4-chlorophenyl)-4,5-dihydro-1H-imidazole and 2-(4-chlorophenyl)-1,4,5,6-tetrahydropyrimidine in the presence of the corresponding ethylenediamine and 1,3-diaminopropane.

NRF2 Activation by Nitrogen Heterocycles: A Review

Several nitrogen heterocyclic analogues have been applied to clinical practice, and about 75% of drugs approved by the FDA contain at least a heterocyclic moiety. Thus, nitrogen heterocycles are beneficial scaffolds that occupy a central position in the development of new drugs. The fact that certain nitrogen heterocyclic compounds significantly activate the NRF2/ARE signaling pathway and upregulate the expression of NRF2-dependent genes, especially HO-1 and NQO1, underscores the need to study the roles and pharmacological effects of N-based heterocyclic moieties in NRF2 activation. Furthermore, nitrogen heterocycles exhibit significant antioxidant and anti-inflammatory activities. NRF2-activating molecules have been of tremendous research interest in recent times due to their therapeutic roles in neuroinflammation and oxidative stress-mediated diseases. A comprehensive review of the NRF2-inducing activities of N-based heterocycles and their derivatives will broaden their therapeutic prospects in a wide range of diseases. Thus, the present review, as the first of its kind, provides an overview of the roles and effects of nitrogen heterocyclic moieties in the activation of the NRF2 signaling pathway underpinning their antioxidant and anti-inflammatory actions in several diseases, their pharmacological properties and structural-activity relationship are also discussed with the aim of making new discoveries that will stimulate innovative research in this area.

Synthesis and Evaluation on the Fungicidal Activity of S-Alkyl Substituted Thioglycolurils

A series of S-alkyl substituted thioglycolurils was prepared through the alkylation of corresponding thioglycolurils with halogenoalkanes and tested for their fungicidal activity against six phytopathogenic fungi from different taxonomic classes: Venturia inaequalis, Rhizoctonia solani, Fusarium oxysporum, Fusarium moniliforme, Bipolaris sorokiniana, and Sclerotinia sclerotiorum, and two pathogenic yeasts: Candida albicans and Cryptococcus neoformans var. grubii. A number of S-alkyl substituted thioglycolurils exhibited high activity against Venturia inaequalis and Rhizoctonia solani (85–100% mycelium growth inhibition), and moderate activity against other phytopathogens. S-Ethyl substituted thioglycolurils possessed a high activity against Candida albicans. Additionally, the hemolytic and cytotoxic properties of promising derivatives were determined using human red blood cells and human embryonic kidney cells, respectively. Two S-ethyl derivatives possessed both low cytotoxicity against normal human cells and high fungicidal activity against Candida albicans.

Red-shifted and pH-responsive imidazole-based azo dyes with potent antimicrobial activity

A novel route is described to obtain 2-aminoimidazole azo dyes with a unique substituent pattern in the heteroaryl unit that provides halochromic properties, exhibiting vibrant colours that change from magenta to deep blue. Potent antimicrobial properties against infectious yeasts were demonstrated. No cytotoxicity was detected for concentrations lower than 16 μg mL^-1.

p53 as a potential target for treatment of cancer: A perspective on recent advancements in small molecules with structural insights and SAR studies

Cancer represents one of the world's biggest hazardous diseases. p53 is the uttermost researched tumour suppressor protein. It is commonly considered the "guardian of the genome," performing a critical function in genetic stability maintenance through controlling the cell cycle, programmed cell death, DNA repair, aging, and angiogenesis. The abnormalities in p53 lead to genetic instability and plays a significant role in carcinogenesis. The role of p53 in tumour suppression is emphasized in addition by the observation that primary silencing with this protein occurred in more than 50% of cancers. MDM2, p53, and the p53-MDM2 connections are well-known targets for the prevention and treatment of cancer. Moreover, in tumors with wild-type p53, their efficacy is decreased due to MDM2 enlargement or by the gradual decrease of MDM2 blocker ARF. As a result, improving p53 activity in cancerous cells provides a promising anticancer strategy. Various techniques are now being investigated, and addressing the p53-MDM2 interaction had also evolved as a potentially feasible strategy for contending with tumors. Both p53 and MDM2, interact via an autoregulation response signal: p53 activity induces MDM2 transcription, which in response interacts with p53's N-terminal transactivation domain, inhibiting its transcriptional activity. This article provides information on the current scenario of anti-tumor activities, with a particular emphasis on structure-activity relationship characteristics (SAR) against the p53-MDM2 to treat cancer. The primary purpose of this review is to cover recent advancements in the creation and testing of anticancer drugs that target the p53-MDM2 structure. This review contains different heterocyclic moieties which show significant results toward cancer. A mechanistic route is shown here, demonstrating both normal and malignant conditions via several stressed factors. Several compounds entered clinical trials as p53-MDM2 inhibitors for the treatment of cancer.