A novel of quinoxaline derivatives tagged with pyrrolidinyl scaffold as a new class of antimicrobial agents: Design, synthesis, antimicrobial activity, and molecular docking simulation

Discovery and optimization of 2-pyridones as dual h-DHFR/EGFRTK inhibitors with immunomodulatory potential; design, synthesis, anti-proliferative activity, and apoptosis inducer

Liver and colorectal cancers present considerable health challenges, underscoring the need to identify innovative targeted therapeutics. Tumor progression can be prevented by targeting EGFR-TK and h-DHFR as essential molecular targets. In this context, we synthesized a new series of 2-pyridones from the reaction of 2-cyanoacrylamide with active methylene or 2-cyanoacetanilide with activated double bonds under basic conditions. The structure of the synthesized 2-pyridones was confirmed through microanalysis and spectroscopic data. In comparison to doxorubicin, the spiro 2-pyridine derivative 9b exhibited the highest anti-proliferative activity, demonstrating IC50 values of 6.89 ± 0.4 μM and 5.68 ± 0.3 μM against HepG-2 and Caco-2 cell lines, respectively, with nearly 2-fold increase in efficacy observed in Caco-2 cells. Additionally, compound 9b demonstrated a significant safety profile concerning normal cells (WI-38), as indicated by selectivity index values of 14.66 and 12.09 against the Caco-2 and HepG-2 cell lines, respectively. Moreover, flow cytometry analysis revealed that compound 9b halted the cell cycle at the G1/S phase in Caco-2 treated cells, demonstrating an increase in the percentage of cells undergoing both early and late apoptosis. The apoptotic potential was corroborated by the up-regulation of BAX and the down-regulation of Bcl-2 levels. Compound 9b exhibited significant inhibitory activity against h-DHFR, with an IC50 value of 0.192 ± 0.011 μM, compared to methotrexate (IC50 = 0.191 ± 0.011 μM). Furthermore, compound 9b demonstrated EGFR inhibitory activity, with IC50 of 0.109 ± 0.005 μM, which is close to the inhibition observed with Lapatinib (IC50 = 0.044 ± 0.002 μM). Compound 9b had better immunomodulatory properties with significant inhibitory efficacy on TNF-α and IL-6, with IC50 values of 0.40 ± 0.03 pg/mL and 0.60 ± 0.02 pg/mL, respectively. These values indicate a greater potency than the positive control drug Lapatinib, which displayed IC50 values of 0.41 ± 0.03 pg/mL and 0.74 ± 0.05 pg/mL for TNF-α and IL-6, respectively. In addition, in silico metabolism prediction using SwissADME and BioTransformer tools revealed that compound 9b is a potential inhibitor of CYP2C9 and CYP3A4, and is predicted to undergo metabolic transformations primarily via aromatic hydroxylation and ketone reduction, while maintaining acceptable stability of its ester moiety. Finally, the molecular docking assessment, together with the direct in vitro enzymatic inhibition results, confirmed that the 2-pyridone derivative 9b can potently bind to and inhibit both EGFR and h-DHFR through favorable binding interactions.

Unveiling a novel pyrazolopyrimidine scaffold as a dual COX-2/5-LOX inhibitor with immunomodulatory potential: Design, synthesis, target prediction, anti-inflammatory activity, and ADME-T with docking simulation

Dual-target COX-2/5-LOX inhibitors are regarded as a rational strategy for the design of potent anti-inflammatory agents with favorable safety profiles. In this study, novel pyrazolo[1,5-a]pyrimidine derivatives were synthesized, developed, and screened for their ability to inhibit the cyclooxygenase-2 enzyme in vitro, with comparisons made to the established inhibitors Celecoxib and Meloxicam. Spectroscopic analyses confirmed the structure of the designed derivatives. The target prediction using AI was performed to identify potential targets that could be engaged through Swiss target prediction database. The SAR study was established by incorporating various substituents and nuclei into the pyrazolopyrimidine pharmacophore. The synthesized pyrazolopyrimidines exhibited IC50 values ranging from 53.32 ± 4.43 to 254.90 ± 6.45 nM, in comparison to Celecoxib (IC50 = 6.73 ± 5.69 nM) and Meloxicam (IC50 = 52.35 ± 6.66 nM). Notably, compound 5a was identified as the most active derivative, demonstrating an IC50 of 53.32 ± 4.43 nM. The three most prominent pyrazolopyrimidine derivatives, 3a, 5a, and 6a, were subsequently evaluated for their ability to inhibit the COX-1 and 5-LOX enzymes. Compounds 3a, 5a, and 6a demonstrated inhibitory activity against COX-1, with IC50 values of 476.45 ± 16.56, 757.51 ± 2.61, and 169.13 ± 5.77 nM, respectively. These derivatives 3a, 5a, and 6a showed significant selectivity index values of 7.91, 14.20, and 2.80, respectively, toward COX-2 rather than COX-1 in comparison to Meloxicam (SI = 0.75) and Celecoxib (SI = 2.35). Moreover, compound 5a exhibited 86 % inhibition compared to Zileuton's 88 %, while compounds 3a and 6a displayed inhibition rates of 84 % and 80 %, respectively, at a concentration of 100 μM. The most potent compound 5a, demonstrated the highest 5-LOX inhibitory activity, with IC50 of 2.292 ± 0.14 μM. The most promising pyrazolopyrimidine derivative 5a demonstrated a down-regulation of TNF-α and IL-6 gene expression by approximately 0.3826-fold and 0.2732-fold, respectively, when compared to Celecoxib, which induced reductions of 0.2320-fold and 0.2730-fold in these cytokines to promote apoptosis in RAW264.7 cells. Finally, in-silico ADME-T and docking simulations were conducted to predict the oral bioavailability, toxicity, and binding interactions with binding affinity.

Antimicrobial activity, synthesis, and docking study of some novel arylazo-1,3-thiazolopyrimidine and arylazo-1,3-thiazolopyridopyrimidine derivatives

In this study, a new series of aryl azo thiazolopyrimidine and thiazolopyridopyrimidine derivatives was synthesized using novel 6-aryl-4-(2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-9-yl)-3,4-dihydropyrimidine-2(1H)-thione and 5-aryl-7-(2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-9-yl)-2-thioxo-2,3-dihydropyrido[2,3-d]pyrimidin-4(1H)-one scaffolds as key intermediates. Structural elucidation of all intermediates and final products was performed via IR, UV, 1H/13C-NMR, and mass spectrometry. Among the forty synthesized compounds, several exhibited significant in vitro antimicrobial activities, particularly derivatives 11a, 11b, 7a, and 7b, with potent inhibition against S. aureus, E. coli, and C. albicans. Molecular docking studies using the bacterial DNA gyrase B subunit (Protein Data Bank (PDB): 1aj6) revealed favorable binding interactions, especially for 11b, which demonstrated the best docking score and strong π-H interactions. Furthermore, DFT-based molecular modeling confirmed the stability and high electronic reactivity of selected bioactive compounds, with low HOMO-LUMO energy gaps and favorable electrostatic potential profiles. Structure-activity relationship (SAR) analysis indicated that electronic effects, lipophilicity, and heteroaromatic substitution patterns critically influence antimicrobial potency. These findings support the potential of thiazolopyridopyrimidine derivatives as promising scaffolds for future antimicrobial drug development.

Assessment of novel 1,2,3,4-tetrahydroquinoline-triazole hybrids compounds as inhibitors of E. coli DNA GyraseB: in vitro and in silico investigation

Ten novel 1,2,3,4-tetrahydroquinolone-triazole compounds (denoted as 6a-6j) were synthesized using click chemistry. These compounds were thoroughly characterized using various analytical techniques, such as FT-IR, mass spectrometry,1H NMR, and 13C NMR. To gather a deeper understanding regarding structural properties of the synthesized compounds, we conducted Density Functional Theory (DFT) studies employing the B3LYP/6-311G (d,p) methodology. These calculations allowed us to evaluate important properties such as the HOMO-LUMO energy gap, chemical potential (µ), electrophilicity (ω), chemical hardness (η), dipole moment (Debye), and total energy (a.u.) for the synthesized hybrids. Moving on to the practical application of these hybrids, we evaluated in vitro antimicrobial inhibitory potential against two gram-positive and two gram-negative strains, and three fungal strains. Obtained outcomes revealed a range of antibacterial activity, with some compounds exhibiting excellent to moderate efficacy. Compounds 6b and 6i showed a very good result with a MIC of 12.5 μg/mL compared to standard Ciprofloxacin (MIC 25 μg/mL), demonstrating strong antibacterial activity against E. coli among the 6a-6j compounds. Furthermore, in silico docking validated our compounds' interaction with E. coli DNA gyrase B. Further, a 200 ns simulation revealed that the promising compounds maintained stability within the binding cavity, with RMSD values below 3 Å, and exhibited reduced structural fluctuations compared to the Apo protein, as evidenced by lower average RMSF values in the ligand-protein complexes. Additionally, an in silico ADME study assessed the drug-likeness of the hybrids, offering insights for future drug development.

Facile phyto-mediated synthesis of ternary CuO/Mn3O4/ZnO nanocomposite using Nigella Sativa seeds extract: characterization,antimicrobial, and biomedical evaluations

The phyto-synthesis of ternary CuO/ Mn3O4/ZnO nanocomposite was achieved by the utilization of an eco-friendly, straightforward approach that involved the extract of Nigella sativa seeds. Our ternary nanocomposite appears to include equal amounts of CuO, Mn3O4, and ZnO based on the atomic percentages. The results indicate that a robust and thermally stable CuO/Mn3O4/ZnO nanocomposite was developed in stable nanosuspensions. The CuO/Mn3O4/ZnO nanocomposites showed antimicrobial capabilities against multidrug-resistant human pathogens. The highest biofilm reduction in viable planktonic populations of all human pathogens investigated was significantly reduced by the CuO/Mn3O4/ZnO ternary nanocomposites with a value of 18.5 µg/mL. The unique, enhanced, and triple-combined properties enabled the nanocomposite to have strong antimicrobial ability. The CuO/Mn3O4/ZnO nanocomposite exhibited strong anticancer activity against A549, MDA, HCT-116, and HepG2 cells, with selectivity index values ​​ranging from 24.72 to 41.96. The CuO/Mn3O4/ZnO nanocomposite appeared to induce selective dose-dependent nuclear condensation and cell shrinkage in the treated cancer cells, significantly inducing the apoptosis mechanism to combat cancer progression. The phytosynthetic CuO/Mn3O4/ZnO nanocomposite appears to induce selective dose-dependent nuclear condensation and cell shrinkage in treated cancer cells, significantly triggering apoptotic mechanisms to combat cancer progression. This apoptotic pathway was confirmed by the strong affinity of CuO/Mn3O4/ZnO nanocomposites for ErbBs and VEGF with potent antioxidant activity to scavenge ABTS and DPPH radicals at EC50 values ​​of 236.6 µg/mL and 134.8 µg/mL, respectively.

A systematic review on the anti-microbial activities and structure-activity relationship (SAR) of quinoxaline derivatives

Anti-microbial resistance has become a serious global health issue affecting millions of people worldwide. Despite extensive drug discovery efforts aimed at identifying potent molecules for effective anti-microbial treatments, the emergence of superbugs remains a significant challenge. Thus, developing novel therapeutic agents is required to combat these evolving threats. The quinoxaline scaffold emerges as a promising heterocyclic framework for developing novel anti-microbial agents. It's simple, flexible structure, coupled with its bioisosteric relationship to extensively explored quinoline and naphthalene scaffolds, offers a potential avenue for circumventing bacterial resistance developed against these established classes. Hence it has sparked interest in researchers to develop novel antibiotics based on the quinoxaline core. This review focuses on the recent advances of quinoxaline derivatives as anti-microbial agents and their structure-activity relationship studies based on the literature published from 2015 to 2024. The systematic presentation of this information will assist researchers in identifying key substitution patterns around the quinoxaline nucleus, facilitating the development of structure-activity relationship (SAR), and guiding the design of novel anti-microbial drugs to combat the growing threat of anti-microbial resistance.

Novel 3-Substituted-2H-Chromene Scaffold Based Fluorinated Hydrophobic Fragment as In-Vitro Antiproliferative Agents and Apoptosis Inducers Targeting Both VEGFR-2/BRAFV600E and h-DHFR With Molecular Docking Simulation

Recently, there has been an increasing interest in the use of protein kinase inhibitors as a therapeutic strategy for the treatment of cancer. In this study, a new series of 2H-chromene derivatives (2-5 and 6-8) and 3H-benzo[f]chromene carbohydrazide derivative (9) were synthesized. The structure of the designed derivatives was characterized by IR, 1H/13C NMR, and elemental analysis. Moreover, the cytotoxic activity of the newly synthesized chromenes was evaluated against breast cancer cell lines (MDA-MB-231 and MCF-7) and a cervical cancer cell line (HeLa). The results of these evaluations demonstrated promising activity, ranging from good to moderate. Additionally, the lung fibroblast cell line (WI-38), as a normal cell line, was also utilized to assess the active derivatives' selectivity. Among the compounds tested, chromene derivative 3 demonstrated the highest potency, exhibiting IC50 values of 5.36 ± 0.50, 7.82 ± 0.60, and 9.28 ± 0.70 µM against the MDA-MB 231, MCF-7, and HeLa cell lines, respectively. The potential of chromone 3 as a multi-targeted anticancer agent was assessed by evaluating its activity against BRAF and VEGFR-2. Notably, the most promising chromene derivative 3 demonstrated significant VEGFR2 activity with an IC50 value of 0.224 µM compared to sorafenib's 0.045 µM, while exhibiting inhibitory activity against BRAF with an IC50 value of 1.695 µM relative to Vemurafenib's IC50 value of 0.468 µM. In addition, compound 3 inhibits the DHFR enzyme with an IC50 value of 2.217 ± 0.014 µM, compared to methotrexate (IC50 = 0.4315 ± 0.019 µM). These results revealed that the compound has multifaceted mechanisms of action that may augment its therapeutic effectiveness. In addition, compound 3 causes overexpression of caspase-3 and Bax by 6.13 and 8.85-fold, respectively. It also downregulates the antiapoptotic Bcl-2 level by 0.4775-fold compared to the untreated MDA-MB 231 cells. Flow cytometry analysis of MDA-MB-231 cells indicates that compound 3 induces cell cycle arrest in the G0-G1 phase, with an observed percentage of 73.15%. The in-silico toxicity prediction was evaluated and demonstrated a good toxicity profile. Finally, molecular docking studies supported these findings by confirming strong binding affinities of the derivatives to VEGFR-2, BRAF, and DHFR.

Recent advances in the synthesis, reaction, and bio-evaluation potential of purines as precursor pharmacophores in chemical reactions: a review

Purines are nitrogenous heterocyclic compounds characterized by the presence of two fused rings: pyrimidine and imidazole. Their significance is underscored by their widespread occurrence in natural products as the metabolic processes of all living organisms heavily rely on purines and their synthetic derivatives. Furthermore, purines exhibit considerable bioactivity, highlighting their importance in biological systems. Given their unique structural characteristics and ability to yield a diverse array of bioactive molecules, purines have attracted substantial attention from researchers. This review illustrates the recent methods for the synthesis of purines from diaminomaleonitrile, urea derivatives, imidazole, and pyrimidine derivatives reported from 2019 to 2024. Additionally, it elucidates the various chemical modifications applied to the purine nucleus, including benzoylation, alkylation, halogenation, amination, selenylation, thiolation, condensation, diazotization, coupling reactions, and other miscellaneous reactions. Moreover, this review discusses several biological evaluations, including the mechanisms of action of purine derivatives as anticancer, antimicrobial, anti-inflammatory, antiviral, antioxidant, and anti-Alzheimer agents. This review aims to assist researchers in synthetic organic and medicinal chemistry toward the development and enhancement of novel methodologies for the synthesis of new purine molecules while supporting biologists in the identification of new targets for bio-evaluation.

Synthesis and modification of novel thiazole-fused quinoxalines as new insecticidal agents against the cotton leafworm Spodoptera litura: design, characterization, in vivo bio-evaluation, toxicological effectiveness, and study their mode of action

Herein, novel thiazolo[4,5-b]quinoxalin-2-ones 2-6 and thiazolo[4,5-b]quinoxalin-2(3H)-imines 7-9 were synthesized and characterized using elemental analysis, IR spectroscopy, and 1H/13C NMR to confirm their structures. The efficacy of the newly designed thiazolo-quinoxalines 2, 3, 4, 5, 7, 8, and 9 against the cotton leafworm S. litura (2nd and 4th instar larvae) was evaluated, and results revealed insecticidal activity with variable and good mortality percentages. A SAR study was also discussed. Additionally, compound 3 exhibited the highest insecticidal activity, with mortality% values ranging from 86% ± 7.21% to 97% ± 1.52% and from 66.00% ± 6.24% to 86.33% ± 6.90% at concentrations of 625-2500 mg L-1 against the 2nd and 4th instar larvae, respectively. The probit analysis revealed that the thiazolo[4,5-b]quinoxalin-2(3H)-one derivative 3, after 5 days of treatment, exhibited LC50 values of 141.02 and 366.73 mg L-1 for the 2nd and 4th instar larvae, respectively. The LT50 values ranged from 0.52 to 1.92 days for the 2nd larval instar and from 1.95 to 2.47 days for the 4th larval instar. The corresponding toxicity index (TI) values were 86.21% for the 2nd instar and 78.47% for the 4th instar larvae. The mode of action of compound 3 was assessed through physiological, histological, and SEM analyses on the 4th larval instar. The physiological bioassay revealed a significant increase in total carbohydrate and protein levels compared to the control group. However, the enzymatic study showed a significant decrease (P < 0.05) in the levels of aspartate aminotransferase (AST/GOT), alanine aminotransferase (ALT/GPT), and alkaline phosphatase (AlP), while acetylcholinesterase (AChE) levels significantly increased. SEM analysis revealed malformations in the external body, while histological examination demonstrated severe damage to the gut epithelium and regenerative cells in the midgut tissues.

Exploring quinoxaline derivatives: An overview of a new approach to combat antimicrobial resistance

Antimicrobial resistance (AMR) has emerged as a long-standing global issue ever since the introduction of penicillin, the first antibiotic. Scientists are constantly working to develop innovative antibiotics that are more effective and superior. Unfortunately, the misuse of antibiotics has resulted in their declining effectiveness over the years. By 2050, it is projected that approximately 10 million lives could be lost annually due to antibiotic resistance. Gaining insight into the mechanisms behind the development and transmission of AMR in well-known bacteria including Escherichia coli, Bacillus pumilus, Enterobacter aerogenes, Salmonella typhimurium, and the gut microbiota is crucial for researchers. Environmental contamination in third world and developing countries also plays a significant role in the increase of AMR. Despite the availability of numerous recognized antibiotics to combat bacterial infections, their effectiveness is diminishing due to the growing problem of AMR. The overuse of antibiotics has led to an increase in resistance rates and negative impacts on global health. This highlights the importance of implementing strong antimicrobial stewardship and improving global monitoring, as emphasized by the World Health Organization (WHO) and other organizations. In the face of these obstacles, quinoxaline derivatives have emerged as promising candidates. They are characterized by their remarkable efficacy against a broad spectrum of harmful bacteria, including strains that are resistant to multiple drugs. These compounds are known for their strong structural stability and adaptability, making them a promising and creative solution to the AMR crisis. This review aims to assess the effectiveness of quinoxaline derivatives in treating drug-resistant infections, with the goal of making a meaningful contribution to the global fight against AMR.

Unveiling anti-diabetic potential of new thiazole-sulfonamide derivatives: Design, synthesis, in vitro bio-evaluation targeting DPP-4, α-glucosidase, and α-amylase with in-silico ADMET and docking simulation

Diabetes mellitus type 2 (T2DM) can be managed by targeting dipeptidyl peptidase-4 (DPP-4), an enzyme that breaks down and deactivates peptides such as GIP and GLP-1. In this context, a new series of 2-(2-substituted hydrazineyl)thiazole derivatives 4, 5, 6, 8, 10, and 11 conjugated with the 2-hydroxy-5-(pyrrolidin-1-ylsulfonyl)benzylidene fragment were designed and synthesized. The virtual screening of the designed derivatives inside DPP-4 demonstrated good to moderate activity, with binding affinity ranging from -6.86 to -5.36 kcal/mol compared to Sitagliptin (S=-5.58 kcal/mol). These results encourage us to evaluate DPP-4 using in-vitro fluorescence-based assay. The in-vitro results exhibited inhibitory percentage (IP) values ranging from 40.66 to 75.62 % in comparison to Sitagliptin (IP=63.14 %) at 100 µM. Subsequently, the IC50 values were determined, and the 5-aryl thiazole derivatives 10 and 11 revealed strong potent IC50 values 2.75 ± 0.27 and 2.51 ± 0.27 µM, respectively, compared to Sitagliptin (3.32 ± 0.22 µM). The SAR study exhibited the importance of the substituents on the thiazole scaffold, especially with the hydrophobic fragment at C5 of the thiazole, which has a role in the activity. Compounds 10 and 11 were further assessed toward α-glucosidase and α-amylase enzymes and give promising results. Compound 10 showed good activity against α-glucosidase with IC50 value of 3.02 ± 0.23 µM compared to Acarbose 3.05 ± 0.22 µM and (11 = 3.34 ± 0.10 µM). On the other hand, for α-amylase, compound 11 was found to be most effective with IC50 value of 2.91 ± 0.23 µM compared to compound 10 = 3.30 ± 0.16 µM and Acarbose (2.99 ± 0.21 µM) indicating that these derivatives could reduce glucose by more than one target. The most active derivatives 10 and 11 attracted great interest as candidates for oral bioavailability and safe toxicity profiles compared to positive controls. The in-silico docking simulation was performed to understand the binding interactions inside the DPP-4, α-glucosidase, and α-amylase pockets, and it was found to be promising antidiabetic agents through a number of interactions.

Discovery of new anti-diabetic potential agents based on paracetamol incorporating sulfa-drugs: Design, synthesis, α-amylase, and α-glucosidase inhibitors with molecular docking simulation

Uncontrolled diabetes can lead to hyperglycemia, which causes neuropathy, heart attacks, retinopathy, and nervous system damage over time, therefore, controlling hyperglycemia using potential drug target inhibitors is a promising strategy. This work focused on synthesizing new derivatives via the diazo group, using a hybridization strategy involving two approved drugs, paracetamol and several sulfonamides. The newly designed diazo-paracetamols 5-12 were fully characterized and then screened for in vitro α-amylase and α-glucosidase activities and exhibited inhibitory percentages (IP) = 92.5-96.5 % and 91.0-95.7 % compared to Acarbose IP = 96.5 and 95.8 %, respectively at 100 μg/mL. The IC50 values of the synthesized derivatives were evaluated against α-amylase and α-glucosidase enzymes, and the results demonstrated moderate to potent activity. Among the tested diazo-paracetamols, compound 11 was found to have the highest potency activity against α-amylase with IC50 value of 0.98 ± 0.015 μM compared to Acarbose IC50 = 0.43 ± 0.009 μM, followed by compound 10 (IC50 = 1.55 ± 0.022 μM) and compound 9 (IC50 = 1.59 ± 0.023 μM). On the other hand, for α-glucosidase, compound 10 with pyrimidine moiety demonstrated the highest inhibitory activity with IC50 = 1.39 ± 0.021 μM relative to Acarbose IC50 = 1.24 ± 0.029 μM and the order of the most active derivatives was 10 > 9 (IC50 = 2.95 ± 0.046 μM) > 11 (IC50 = 5.13 ± 0.082 μM). SAR analysis confirmed that the presence of 4,5-dimethyl-isoxazole or pyrimidine nucleus attached to the sulfonyl group is important for activity. Finally, the docking simulation was achieved to determine the mode of binding interactions for the most active derivatives in the enzyme's active site.

Design and Synthesis of Novel Fluorescent 2-(aryloxy)-3-(4,5-diaryl)-1H-imidazol-2-yl)quinolines: Solvatochromic, DFT, TD-DFT Studies, COX-1 and COX-2 Inhibition and Antioxidant Properties

The present work focuses on the synthesis of novel heterocycles 2-(aryloxy)-3-(4,5-diaryl-1H-imidazol-2-yl)quinolines (6k-v) by an effective condensation reaction. These molecules exhibited fluorescent properties and hence for the proper understanding of their optical behavior and quantum yields, solvatochromic studies have been carried out. Further, frontier molecular orbitals, molecular electrostatic potential (MEP), and geometrical structure optimization have been investigated using the B3LYP/6-311G ++ (d, p) method. The energy gap between the HOMO, LUMO of the optical and energy band gap is determined by DFT and UV-visible spectra for TD-DFT studies are done. The screening of these compounds for in vitro COX-1 and COX-2 inhibition and DPPH free radical scavenging ability assays produced promising results. The binding interactions of these molecules against the COX-2 enzyme (PDB: 5IKR) were validated by docking studies.

Discovery of novel 6-(piperidin-1-ylsulfonyl)-2H-chromenes targeting α-glucosidase, α-amylase, and PPAR-γ: Design, synthesis, virtual screening, and anti-diabetic activity for type 2 diabetes mellitus

A new series of 2H-chromene-based sulfonamide derivatives 3-12 has been synthesized and characterized using different spectroscopic techniques. The synthesized 2H-chromenes were synthesized by reacting activated methylene with 5-(piperidin-1-ylsulfonyl)salicylaldehyde through one-step condensation followed by intramolecular cyclization. Virtual screening of the designed molecules on α-glucosidase enzymes (PDB: 3W37 and 3A4A) exhibited good binding affinity suggesting that these derivatives may be potential α-glucosidase inhibitors. In-vitro α-glucosidase activity was conducted firstly at 100 µg/mL, and the results demonstrated good inhibitory potency with values ranging from 90.6% to 96.3% compared to IP = 95.8% for Acarbose. Furthermore, the IC50 values were determined, and the designed derivatives exhibited inhibitory potency less than 11 µg/mL. Surprisingly, two chromene derivatives 6 and 10 showed the highest potency with IC50 values of 0.975 ± 0.04 and 0.584 ± 0.02 µg/mL, respectively, compared to Acarbose (IC50 = 0.805 ± 0.03 µg/mL). Moreover, our work was extended to evaluate the in-vitro α-amylase and PPAR-γ activity as additional targets for diabetic activity. The results exhibited moderate activity on α-amylase and potency as PPAR-γ agonist making it a multiplet antidiabetic target. The most active 2H-chromenes 6 and 10 exhibited significant activity to PPAR-γ with IC50 values of 3.453 ± 0.14 and 4.653 ± 0.04 µg/mL compared to Pioglitazone (IC50 = 4.884±0.29 µg/mL) indicating that these derivatives improve insulin sensitivity by stimulating the production of small insulin-sensitive adipocytes. In-silico ADME profile analysis indicated compliance with Lipinski's and Veber's rules with excellent oral bioavailability properties. Finally, the docking simulation was conducted to explain the expected binding mode and binding affinity.

Antifungal Activity of 3-Hydrazinoquinoxaline-2-Thiol, a Novel Quinoxaline Derivative against Candida Species

Candida ranks as among the most frequently encountered fungal infections that associated with high morbidity and mortality. Quinoxaline derivatives are a group of small molecules that showed a promising antimicrobial activity. This study aimed to investigate the fungicidal effects of 3-hydrazinoquinoxaline-2-thiol against Candida in comparison with Amphotericin B in vitro as a reference. Also, we aim to assess the efficacy of 3-hydrazinoquinoxaline-2-thiol in vivo using mice oral candidiasis model. Fifty-six Candida isolates were subjected to susceptibility testing by broth microdilution method for 3-hydrazinoquinoxaline-2-thiol and Amphotericin B. Therefore, Minimal inhibitory concentrations (MIC) were assessed and compared. The oral candidiasis mice model was used to evaluate the activity of 3-hydrazinoquinoxaline-2-thiol in vivo. Microbiological evaluation of progression and ELISA were used in this study. 3-hydrazinoquinoxaline-2-thiol was more effective than Amphotericin B against most clinical isolates of Candida albicans. Higher effectiveness was seen against Candida glabrata and Candida parapsilosis isolates. However, the efficiency against Candida tropicalis isolates varies. 3-hydrazinoquinoxaline-2-thiol was also effective against Pichia kudriavzevii and Clavispora lusitaniae. 3-hydrazinoquinoxaline-2-thiol showed a good efficacy in mice model against C. albicans cells ATCC 10231. 3-hydrazinoquinoxaline-2-thiol has shown promising antifungal and anti-inflammatory activity against different Candida species. More tests and experiments are needed.

Explore new quinoxaline pharmacophore tethered sulfonamide fragments as in vitro α-glucosidase, α-amylase, and acetylcholinesterase inhibitors with ADMET and molecular modeling simulation

A new series of quinoxaline-sulfonamide derivatives 3-12 were synthesized using fragment-based drug design by reaction of quinoxaline sulfonyl chloride (QSC) with different amines and hydrazines. The quinoxaline-sulfonamide derivatives were evaluated for antidiabetic and anti-Alzheimer's potential against α-glucosidase, α-amylase, and acetylcholinesterase enzymes. These derivatives showed good to moderate potency against α-amylase and α-glucosidase with inhibitory percentages between 24.34 ± 0.01%-63.09 ± 0.02% and 28.95 ± 0.04%-75.36 ± 0.01%, respectively. Surprisingly, bis-sulfonamide quinoxaline derivative 4 revealed the most potent activity with inhibitory percentages of 75.36 ± 0.01% and 63.09 ± 0.02% against α-glucosidase and α-amylase compared to acarbose (IP = 57.79 ± 0.01% and 67.33 ± 0.01%), respectively. Moreover, the quinoxaline derivative 3 exhibited potency as α-glucosidase and α-amylase inhibitory with a minute decline from compound 4 and acarbose with inhibitory percentages of 44.93 ± 0.01% and 38.95 ± 0.01%. Additionally, in vitro acetylcholinesterase inhibitory activity for designed derivatives exhibited weak to moderate activity. Still, sulfonamide-quinoxaline derivative 3 emerged as the most active member with inhibitory percentage of 41.92 ± 0.02% compared with donepezil (IP = 67.27 ± 0.60%). The DFT calculations, docking simulation, target prediction, and ADMET analysis were performed and discussed in detail.

The fungicidal effectiveness of 2-Chloro-3-hydrazinylquinoxaline, a newly developed quinoxaline derivative, against Candida species

BACKGROUND

Candida represents a prevalent fungal infection, notable for its substantial implications on morbidity and mortality rates. In the landscape of prospective treatments, quinoxaline derivatives emerge as a category of compact compounds exhibiting notable potential in addressing infections. These derivatives showcase promising antimicrobial efficacy coupled with favorable pharmacokinetic and safety characteristics.

AIMS

The central aim of this investigation was to examine the antifungal characteristics of 2-Chloro-3-hydrazinylquinoxaline against diverse strains of Candida and Aspergillus in vitro. Additionally, we endeavored to assess the in vivo efficacy of 2-Chloro-3-hydrazinylquinoxaline using a murine model for oral candidiasis induced by C. albicans cells ATCC 10231.

RESULTS

2-Chloro-3-hydrazinylquinoxaline demonstrated noteworthy effectiveness when tested against various reference strains of Candida species. It exhibited heightened efficacy, particularly against Candida krusei isolates. However, its performance against Candida albicans, Candida tropicalis, Candida glabrata, Candida parapsilosis, and Candida auris isolates exhibited variability. Notably, 2-Chloro-3-hydrazinylquinoxaline manifests variable efficacy against Aspergillus fumigatus, Aspergillus niger, Aspergillus terreus and Aspergillus flavus and no effect against Aspergillus brasiliensis. In a murine model, 2-Chloro-3-hydrazinylquinoxaline exhibited significant efficacy in combating the C. albicans cells ATCC 10231 strain, underscoring its potential as a viable treatment option.

CONCLUSION

2-Chloro-3-hydrazinylquinoxaline has demonstrated substantial potential in effectively addressing various Candida and Aspergillus species, showcasing dual attributes of antifungal and anti-inflammatory properties. However, to attain a more comprehensive understanding of its therapeutic capabilities, further investigations, incorporating additional tests and experiments, are imperative.

Synthesis, DFT Calculations, In Silico Studies, and Antimicrobial Evaluation of Benzimidazole-Thiadiazole Derivatives

In this study, a series of new benzimidazole-thiadiazole hybrids were synthesized, and the synthesized compounds were screened for their antimicrobial activities against eight species of pathogenic bacteria and three fungal species. Azithromycin, voriconazole, and fluconazole were used as reference drugs in the mtt assay. Among them, compounds 5f and 5h showed potent antifungal activity against C. albicans with a MIC of 3.90 μg/mL. Further, the results of the antimicrobial assay for compounds 5a, 5b, 5f, and 5h proved to be potent against E. faecalis (ATCC 2942) on the basis of an acceptable MIC value of 3.90 μg/mL. The cytotoxic effects of compounds that are effective as a result of their antimicrobial activity on healthy mouse fibroblast cells (L929) were evaluated. According to HOMO-LUMO analysis, compound 5h (with the lower ΔE = 3.417 eV) is chemically more reactive than the other molecules, which is compatible with the highest antibacterial and antifungal activity results. A molecular docking study was performed to understand their binding modes within the sterol 14-α demethylase active site and to interpret their promising fungal inhibitory activities. Molecular dynamics (MD) simulations of the most potent compounds 5f and 5h were found to be quite stable in the active site of the 14-α demethylase (5TZ1) protein.

Utilising UPLC-QTOF-MS/MS to determine the phytochemical profile and in vitro cytotoxic potential of Ziziphora capitata L. with molecular docking simulation

Ziziphora capitata (Lamiaceae family) aerial parts extract contains 57 metabolites, including flavonoids, phenolic acids, anthocyanins, and coumarins, as assessed by UPLC-QTOF-MS/MS. Successive extracts (hexane, chloroform, ethyl acetate, ethanol 95%, and water) were tested in vitro cytotoxic activity against HepG-2, MCF-7, HCT-116, A549, and PC3 cell lines. The results revealed that hexane extract exhibited the most potent cytotoxic activity among PC3 and A549 cell lines, IC50 = 47.1 ± 1.75 and 49.2 ± 1.08 µg/mL compared to Vinblastine IC50 = 42.47 ± 1.95 and 24.64 ± 1.18 µg/mL, respectively, and had a moderate impact on the remaining cell lines. Moreover, the chloroform and ethyl acetate extracts exhibited moderate affinity among all tested cell lines. Furthermore, the total phenolic and flavonoid contents were assessed. The molecular docking simulation was performed inside the effective sites of VEGFR-2 and TS as anticancer targets for the top ten phytochemicals. The results showed higher binding energy values for VEGFR-2 than for TS compared to vinblastine and co-crystallized ligands.

Synthesis of a Series of Quinoxaline Derivatives and Their Antibacterial Effectiveness Against Pathogenic Bacteria

The pharmacological importance of quinoxaline derivatives in antibacterial research is well recognized. This study focuses on the synthesis of new 2,3‐dichloroquinoxaline derivatives containing thioether/ether groups to explore their potential as potent antibacterial agents against various pathogenic bacteria. Most of the compounds exhibited significant antibacterial properties comparable to the standard drug chlorhexidine (CHX). The derivatives of 2‐chloro‐3‐(arylthiol)quinoxaline demonstrated efficacy against Escherichia coli with minimum inhibitory concentrations (MIC) of 2.5 mg/mL and minimum bactericidal concentrations (MBC) of 2.5 to 5.0 mg/mL. These derivatives also showed similar sensitivity to Bacillus pumilus. In addition, molecular docking simulations were performed to investigate the interaction between the synthesized compounds and the DNA gyrase protein (PDB ID: 1KZN), a target for antibiotics. Among the synthesized compounds, 2,3‐bis(3‐nitrophenoxy)quinoxaline exhibited the most favourable docking score of −8.36 kcal/mol, with a binding affinity comparable to that of the reference ligand clorobiocin (−9.3 kcal/mol).

Recent Methods for the Synthesis of Quinoxaline Derivatives and their Biological Activities

Quinoxaline derivatives have been incorporated into numerous marketed drugs used for the treatment of various diseases. Examples include glecaprevir (Mavyret), voxilaprevir (Vosevi), Balversa (L01EX16) (erdafitinib), carbadox, XK469R (NSC698215), and becampanel (AMP397). These quinoxaline derivatives exhibit a diverse range of pharmacological activities, including antibacterial, antitubercular, antiviral, anti-HIV, anti-inflammatory, antifungal, anticancer, antiproliferative, antitumor, kinase inhibition, antimicrobial, antioxidant, and analgesic effects. Recognizing the significance of these bioactive quinoxaline derivatives, researchers have dedicated their efforts to developing various synthetic methods for their production. This review aimed to compile the most recent findings on the synthesis and biological properties of quinoxaline derivatives from 2015 to 2023.

Developing a new multi-featured chitosan-quinoline Schiff base with potent antibacterial, antioxidant, and antidiabetic activities: design and molecular modeling simulation

A new chitosan Schiff base was developed via the reaction of chitosan (CH) with 2-chloro-3-formyl-7-ethoxy quinoline (Q) derivative. The alteration in the chemical structure and morphology of CHQ derivative was confirmed by 1H NMR, FT-IR spectroscopy and SEM analysis. The antibacterial activity was considerably promoted with increasing quinoline concentration up to 1 M with maximal inhibition reached 96 and 77% against Staphylococcus haemolyticus and Escherichia coli, respectively. Additionally, CHQ derivative afforded higher ABTS·+ radical scavenging activity reached 59% compared to 13% for native chitosan, approving its acceptable antioxidant activity. Moreover, the developed CHQ derivative can stimulate the glucose uptake in HepG-2 and yeast cells, while better inhibition of α-amylase and α-glucosidase was accomplished with maximum values of 99.78 and 92.10%, respectively. Furthermore, the molecular docking simulation clarified the binding mode of CHQ derivative inside the active site of α-amylase and α-glucosidase, suggesting its potential use as diabetes mellitus drug. The DFT calculations indicated an improvement in the electronic properties of CHQ with a lower energy band gap reached 4.05eV compared to 5.94eV for CH. The cytotoxicity assay revealed the safety of CHQ towards normal HSF cells, hypothesizing its possible application as non-toxic antibacterial, antioxidant, and antidiabetic agent for biomedical applications.

One-pot synthesis of pyrazolo[4,3-d]thiazole derivatives containing α-aminophosphonate as potential Mur A inhibitors against MDR pathogens with radiosterilization and molecular modeling simulation

The present study involves the synthesis of a new series of α-aminophosphonate derivatives in good yields with a simple workup via the Kabachnik-Fields reaction using lithium perchlorate (LiClO4) as a catalyst to facilitate the reaction. All the newly synthesized compounds were confirmed using various physical, spectroscopic, and analytical data, and the obtained results correlated with the proposed molecular structure. The in vitro antimicrobial activities of each compound were evaluated against different clinical isolates. The results indicated that among these derivatives, two compounds (5a and 5b) were the most active and displayed potent activity with MICs in the range from 0.06 to 0.25 μg mL-1 compared with fosfomycin and fluconazole as standard antibiotics. Moreover, the synthesized phosphonates displayed a broad spectrum of bactericidal and fungicidal activities depending on MICs, MBCs/MFCs, and the time-kill kinetics. In addition, the checkerboard assay showed synergistic and partial synergistic activities between the active compounds combined with fosfomycin and fluconazole. Furthermore, the SEM images showed distinct ruptures of the OM integrity of the FOS-R E. coli at their MICs, which was further indicated by the increased EtBr accumulation within the bacterial cells. Moreover, active derivatives revealed MurA inhibitory activity with IC50 values of 3.8 ± 0.39 and 4.5 ± 0.23 μM compared with fosfomycin (IC50 = 12.7 ± 0.27 μM). To our surprise, exposing 5a and 5b compounds to different gamma radiation doses revealed that 7.0 kGy eradicated the microbial load completely. Finally, the results of quantum chemical study supported the binding mode obtained from the docking study performed inside the active site of MurA (PDB: 1UAE), suggesting that these phosphonates may be promising safe candidates for MDR infection therapy clinical trials with no toxic effects on the normal human cells.

Design, green synthesis, and quorum sensing quenching potential of novel 2-oxo-pyridines containing a thiophene/furan scaffold and targeting a LasR gene on P. aeruginosa

The current trend in fighting bacteria is attacking the virulence and quorum-sensing (QS) signals that control bacterial communication and virulence factors, especially biofilm formation. This study reports new Schiff bases and tetracyclic rings based on a pyridine pharmacophore by two methods: a green approach using CAN and a conventional method. The structure of designed derivatives was confirmed using different spectroscopies (IR and 1H/13C NMR) and elemental analysis. The designed derivatives exhibited good to moderate inhibition zones against bacterial and fungal pathogens. In addition, six compounds 2a,b, 3a,b, and 6a,b displayed potency against tested pathogens with eligible MIC and MBC values compared to standard antimicrobial agents. Compound 2a displayed MIC values of 15.6 μg mL-1 compared to Gentamicin (MIC = 250 μg mL-1 against K. pneumoniae), while compound 6b exhibited super-potent activity against P. aeruginosa, and K. pneumoniae with MIC values of 62.5 and 125 μg mL-1, as well as MBC values of 31.25 and 15.6 μg mL-1 compared to Gentamicin (MIC = 250 and 125 μg mL-1 and MBC = 62.5 μg mL-1), respectively. Surprisingly, these six derivatives revealed bactericidal and fungicidal potency and remarkable anti-biofilm activity that could significantly reduce the biofilm formation against MRSA, E. coli, P. aeruginosa, and C. albicans. Furthermore, the most active derivatives reduced the LasR gene's production between 10-40% at 1/8 MICs compared with untreated P. aeruginosa. Besides, they demonstrated promising safety profile on Vero cells (normal cell lines) with IC50 values ranging between (175.17 ± 3.49 to 344.27 ± 3.81 μg mL-1). In addition, the in silico ADMET prediction was carried out and the results revealed that these compounds could be used with oral bioavailability with low toxicity prediction when administered as a candidate drug. Finally, the molecular docking simulation was performed inside LasR and predicted the key binding interactions responsible for the activity that corroborated the biological results.

Unveiling the antitumor potential of novel N-(substituted-phenyl)-8-methoxycoumarin-3-carboxamides as dual inhibitors of VEGFR2 kinase and cytochrome P450 for targeted treatment of hepatocellular carcinoma

Being the sixth most diagnosed cancer and the fourth leading cause of cancer-related deaths worldwide, liver cancer is considered as a serious disease with a high prevalence and poor prognosis. Current anticancer drugs for liver cancer have drawbacks, such as limited efficacy in later stages of the disease, toxicity to healthy cells, and the potential for drug resistance. There is ample evidence that coumarin-based compounds are potent anticancer agents, with numerous analogues currently being investigated in preclinical and clinical studies. The current study aimed to explore the antitumor potency of a new class of 8-methoxycoumarin-3-carboxamides against liver cancer. Toward this aim, we have designed, synthesized, and characterized a new set of N-(substituted-phenyl)-8-methoxycoumarin-3-carboxamide analogues. The assessment of antitumor activity revealed that the synthesized class of compounds possesses substantial cytotoxicity toward Hep-G2 cells when compared to staurosporine, without significant impact on normal cells. Out of the synthesized compounds, compound 7 demonstrated the most potent cytotoxic effect against Hep-G2 cells with an IC50 of 0.75 µM, which was more potent than the drug staurosporine (IC50 = 8.37 µM). The investigation into the mechanism behind the antiproliferative activity of compound 7 revealed that it interferes with DNA replication and induces DNA damage, leading to cell cycle arrest as demonstrated by a significant decrease in the percentage of cells in the G1 and G2/M phases, along with an increase in the percentage of cells in the S phase. Flow cytometric analysis further revealed that compound 7 has the ability to trigger programmed cell death by inducing necrosis and apoptosis in HepG-2 cells. Further explorations into the mechanism of action demonstrated that compound 7 displays a potent dual-inhibitory activity toward cytochrome P450 and vascular endothelial growth factor receptor-2 (VEGFR-2) proteins, as compared to sorafenib drug. Further, detailed computational studies revealed that compound 7 displays a considerable binding affinity toward the binding cavity of VEGFR2 and CYP450 proteins. Taken together, our findings indicate that the newly synthesized class of compounds, particularly compound 7, could serve as a promising scaffold for the development of highly effective anticancer agents against liver cancer.

A new class of anti-proliferative activity and apoptotic inducer with molecular docking studies for a novel of 1,3-dithiolo[4,5-b]quinoxaline derivatives hybrid with a sulfonamide moiety

A new series of 6-(pyrrolidin-1-ylsulfonyl)-[1,3]dithiolo[4,5-b]quinoxaline-2-ylidines 10a-f, 12, 14, 16, and 18 were designed, synthesized, and evaluated for their in vitro anticancer activity. The structures of the novel compounds were systematically characterized by 1H NMR, 13C NMR, and elemental analysis. The synthesized derivatives were evaluated for their in vitro antiproliferative activity against three human cancer cell lines (HepG-2, HCT-116, and MCF-7) with more sensitivity to MCF-7. Moreover, three derivatives 10c, 10f, and 12 were the most promising candidates with sub-micromole values. These derivatives were further evaluated against MDA-MB-231, and the results displayed significant IC50 values ranging from 2.26 ± 0.1 to 10.46 ± 0.8 μM and showed low cellular cytotoxicity against WI-38. Surprisingly, the most active derivative 12 revealed sensitivity towards the breast cell lines MCF-7 (IC50 = 3.82 ± 0.2 μM) and MDA-MB-231 (IC50 = 2.26 ± 0.1 μM) compared with doxorubicin (IC50 = 4.17 ± 0.2 and 3.18 ± 0.1 M). Cell cycle analysis showed that compound 12 arrests and inhibits the growth of MCF-7 cells in the S phase with values of 48.16% compared with the untreated control 29.79% and exhibited a significantly higher apoptotic effect in MCF-7 with a value of 42.08% compared to control cell at 1.84%. Furthermore, compound 12 decreased Bcl-2 protein 0.368-fold and activation on pro-apoptotic genes Bax and P53 by 3.97 and 4.97 folds, respectively, in MCF-7 cells. Compound 12 exhibited higher inhibitory activity to EGFRWt, EGFRL858R, and VEGFR-2 with IC50 values (0.19 ± 0.009, 0.026 ± 0.001, and 0.42 ± 0.021 μM) compared with erlotinib (IC50 = 0.037 ± 0.002 and 0.026 ± 0.001 μM) and sorafenib (IC50 = 0.035 ± 0.002 μM). Finally, in silico ADMET prediction presented that 1,3-dithiolo[4,5-b]quinoxaline derivative 12 obeys the Lipinski rule of five and the Veber rule with no PAINs alarms and moderately soluble properties. Additionally, toxicity prediction revealed that compound 12 demonstrated inactivity to hepatotoxic carcinogenicity, immunotoxicity, mutagenicity, and cytotoxicity. Moreover, molecular docking studies showed good binding affinity with lower binding energy inside the active site of Bcl-2 (PDB: 4AQ3), EGFR (PDB: 1M17), and VEGFR (PDB: 4ASD).

Exploring novel derivatives of isatin-based Schiff bases as multi-target agents: design, synthesis, in vitro biological evaluation, and in silico ADMET analysis with molecular modeling simulations

Recently, scientists developed a powerful strategy called "one drug-multiple targets" to discover vital and unique therapies to fight the most challenging diseases. Novel derivatives of isatin-based Schiff bases 2-7 have been synthesized by the reaction of 3-hydrazino-isatin (1) with aryl aldehydes, hetero-aryl aldehydes, and dialdehydes. The structure of the synthesized derivatives was proved by physical and spectral analysis. Additionally, in vitro biological studies were performed, including antioxidant, anti-diabetic, anti-Alzheimer, and anti-arthritic activities. The four derivatives 3b, 5a, 5b, and 5c possess the highest activities. Among the four potent derivatives, compound 5a exhibited the highest antioxidant (TAC = 68.02 ± 0.15 mg gallic acid per g; IRP = 50.39 ± 0.11) and scavenging activities (ABTS = 53.98 ± 0.12% and DPPH = 8.65 ± 0.02 μg mL-1). Furthermore, compound 5a exhibited an α-amylase inhibitory percentage of 57.64 ± 0.13% near the acarbose (ACA = 69.11 ± 0.15%) and displayed inhibitor activity of the acetylcholinesterase (AChE) enzyme = 36.38 ± 0.08%. Moreover, our work extended to determining the anti-arthritic effect, and compound 5a revealed good inhibitor activities with very close values for proteinase denaturation (PDI) = 39.59 ± 0.09% and proteinase inhibition (PI) = 36.39 ± 0.08%, compared to diclofenac sodium PDI = 49.33 ± 0.11% and PI = 41.88 ± 0.09%. Additionally, the quantum chemical calculations, including HOMO, LUMO, and energy band gap were determined, and in silico ADMET properties were predicted, and their probability was recorded. Finally, molecular docking simulations were performed inside α-amylase and acetylcholinesterase enzymes.

Development of novel pyrazole, imidazo[1,2-b]pyrazole, and pyrazolo[1,5-a]pyrimidine derivatives as a new class of COX-2 inhibitors with immunomodulatory potential

Searching for new compounds with anti-inflammatory properties is a significant target since inflammation is a major cause of pain. A series of pyrazole, imidazopyrazolone, and pyrazolopyrimidine derivatives were designed and synthesized by reaction of 3,5-diamino-1H-pyrazole derivative with cyclic and acyclic carbonyl reagents. The structure of the newly synthesized derivatives were fully characterized using different spectroscopic data and elemental analysis, and therefore, evaluated as COX-2 inhibitors. The in vitro COX-2 activity of the tested derivatives 2-13 displayed moderate to good potency with two derivatives 8 and 13 that exhibiting high potency to COX-2 with IC₅₀ values of 5.68 ± 0.08 and 3.37 ± 0.07 μM compared with celecoxib (IC₅₀ = 3.60 ± 0.07 μM) and meloxicam (IC₅₀ = 7.58 ± 0.13 μM). Furthermore, the most active pyrazolo[1,5-a]pyrimidine derivatives 8 and 13 were evaluated to measure the levels of pro-inflammatory proteins such as TNF-α and IL-6 using qRT-PCR in RAW264.7 cells, and the results showed down-regulation of two immunomodulatory proteins. Surprisingly, these derivatives 8 and 13 revealed a decrease in IL-6 level with inhibition percentages of 65.8 and 70.3%, respectively, compared with celecoxib (% = 76.8). Further, compounds 8 and 13 can regulate and suppress the TNF-α with percentage inhibition of 63.1 and 59.2% to controls, while celecoxib displayed an inhibition percentage of 72.7. The Quantum chemical calculation was conducted, and data explained the structural features crucial to the activity. The molecular docking simulation and ADMET predictions revealed that the most active derivatives have good binding affinity, possess appropriate drug-likeness properties and low toxicity profiles. Finally, compounds 8 and 13 demonstrated COX-2 inhibitors with α-TNF and IL-6 suppression capabilities as a dual-action strategy to get more effective treatment.

Antibiofilm and Anti-Quorum-Sensing Activities of Novel Pyrazole and Pyrazolo[1,5-a]pyrimidine Derivatives as Carbonic Anhydrase I and II Inhibitors: Design, Synthesis, Radiosterilization, and Molecular Docking Studies

Nowadays, searching for new anti-infective agents with diverse mechanisms of action has become necessary. In this study, 16 pyrazole and pyrazolo[1,5-a]pyrimidine derivatives were synthesized and assessed for their preliminary antibacterial and antibiofilm activities. All these derivatives were initially screened for their antibacterial activity against six clinically isolated multidrug resistance by agar well-diffusion and broth microdilution methods. The initial screening presented significant antibacterial activity with a bactericidal effect for five compounds, namely 3a, 5a, 6, 9a, and 10a, compared with Erythromycin and Amikacin. These five derivatives were further evaluated for their antibiofilm activity against both S. aureus and P. aeruginosa, which showed strong biofilm-forming activity at their MICs by >60%. The SEM analysis confirmed the biofilm disruption in the presence of these derivatives. Furthermore, anti-QS activity was observed for the five hybrids at their sub-MICs, as indicated by the visible halo zone. In addition, the presence of the most active derivatives reduces the violacein production by CV026, confirming that these compounds yielded anti-QS activity. Furthermore, these compounds showed strong inhibitory action against human carbonic anhydrase (hCA-I and hCA-II) isoforms with IC50 values ranging between 92.34 and 168.84 nM and between 73.2 and 161.22 nM, respectively. Finally, radiosterilization, ADMET, and a docking simulation were performed.

Evaluation of the anti-proliferative activity of 2-oxo-pyridine and 1′H-spiro-pyridine derivatives as a new class of EGFRWt and VEGFR-2 inhibitors with apoptotic inducers†

Developing new agents for cancer treatment remains a top priority because it is one of the deadliest worldwide. A new series of 2-oxo-pyridine and 1′H-spiro-pyridine derivatives were designed and synthesized based on an N-(ethyl benzoate) moiety. The structure of the designed derivatives was confirmed by different spectroscopic techniques (FT-IR and NMR) and elemental analysis and then evaluated as antiproliferative against HepG-2 and Caco-2 cell lines compared with Doxorubicin. The spiro-pyridine derivatives 5, 7, and 8 exhibited a remarkably higher activity against Caco-2 cell lines than that of other derivatives. Additionally, these derivatives exhibited activation in the Bax and suppressed Bcl-2 expression with variable degrees. Interestingly, compound 7 showed the lowest cytotoxicity value on Caco-2 cells (IC₅₀ = 7.83 ± 0.50 μM) compared with Doxorubicin (IC₅₀ = 12.49 ± 1.10 μM). Additionally, this compound showed activation of the Bax gene (7.508-fold) and suppressed Bcl-2 (0.194-fold) compared to untreated Caco-2 cells, as revealed by the qRT-PCR technique. Moreover, compound 7 could inhibit EGFR and VEGFR-2 with sub-micromole values of 0.124 μM and 0.221 μM compared with Erlotinib (IC₅₀ = 0.033 μM) and Sorafenib (IC₅₀ = 0.043 μM), respectively. Further, cell cycle and apoptosis analysis demonstrated that compound 7 promoted apoptosis by increasing the apoptosis rate from 1.92 to 42.35% and the S cell accumulation ratio from 31.18 to 42.07% compared to untreated Caco-2 cells. Finally, the most active compound 7 showed good drug-likeness and toxicity profiles. Besides, molecular docking studies were performed to determine the binding mode, which is in agreement with the in vitro results.

Design and synthesis a novel of 2-oxo-pyridine and 1′H-spiro-pyridine derivatives as a new apoptotic inducers agents.