Nitrogen Containing Heterocycles as Anticancer Agents: A Medicinal Chemistry Perspective

Recent advances on quinoxalines as target-oriented chemotherapeutic anticancer agents through apoptosis

The current review outlines all possible recent synthetic platforms to quinoxaline derivatives and the potent stimulated apoptosis mechanisms targeted by anticancer therapies. The currently reported results disclosed that quinoxaline derivatives had promising anticancer potencies against a wide array of cancer cell lines, better than the reference drugs, through target inhibition. This review summarizes some potent quinoxaline derivatives with their synthesis strategies and their potential activities against various molecular targets. Quinoxalines can be considered an important scaffold for apoptosis inducers in cancer cells through inhibiting some molecular targets, so they can be further developed as target-oriented chemotherapeutics.

BPO-promoted [4 + 2] cyclization of enaminones and o-phenylenediamines to 2-acyl quinoxalines via a cascade transamination and C-H amination

Rapid assembly of quinoxalines in a single step from readily available precursors has been recognized as an ideal platform in terms of efficiency and operation. Herein, we report a BPO-promoted metal-free approach to 2-acyl quinoxalines from enaminones and o-phenylenediamines via cascade transamination and C-H amination. This methodology demonstrates excellent compatibility with various substrates, including o-hydroxy enaminones, drug derivatives and natural products under mild reaction conditions.

Mild and efficient synthesis and base-promoted rearrangement of novel isoxazolo[4,5-b]pyridines

An efficient method for the synthesis of isoxazolo[4,5-b]pyridines has been developed on the basis of readily available 2-chloro-3-nitropyridines via the intramolecular nucleophilic substitution of the nitro group as a key step. The previously unknown base-promoted Boulton-Katritzky rearrangement of isoxazolo[4,5-b]pyridine-3-carbaldehyde arylhydrazones into 3-hydroxy-2-(2-aryl[1,2,3]triazol-4-yl)pyridines was observed.

Medicinal attributes of thienopyrimidine scaffolds incorporating the aryl urea motif as potential anticancer candidates via VEGFR inhibition

Worldwide, cancer is a major public health concern. It is a well-acknowledged life-threatening disease. Despite numerous advances in the understanding of the genetic basis of cancer growth and progression, therapeutic challenges remain high. Human tumors exhibited mutation or overexpression of several tyrosine kinases (TK). The vascular endothelial growth factor receptor (VEGFR) is a TK family member and is well known for tumor growth and progression. Therefore, VEGF/VEGFR pathway inhibition is an appealing approach for cancer drug discovery. This review will discuss the structure-based optimization of thienopyrimidines incorporating the aryl urea moiety to develop scaffolds of potent anticancer activity via VEGFR inhibition published between 2013 and 2023. Increasing knowledge of probable scaffolds that can act as VEGFR inhibitors might spur the hunt for novel anticancer medications that are safer, more effective, or both.

Visible-Light-Driven Decarboxylative Coupling of 2H-Indazoles with α-Keto Acids without Photocatalysts and Oxidants

An efficient synthesis of functionalized 3-acyl-2H-indazoles via visible-light-induced self-catalyzed energy transfer was developed. This method utilized a self-catalyzed energy transfer process between 2H-indazoles and α-keto acids, offering advantages like absence of photosensitizers, metal catalysts, and strong oxidants, broad substrate compatibility, and operational simplicity under mild conditions.

Synthesis, crystal structure and in-silico evaluation of arylsulfonamide Schiff bases for potential activity against colon cancer

This report presents a comprehensive investigation into the synthesis and characterization of Schiff base compounds derived from benzenesulfonamide. The synthesis process, involved the reaction between N-cycloamino-2-sulfanilamide and various substituted o-salicylaldehydes, resulted in a set of compounds that were subjected to rigorous characterization using advanced spectral techniques, including 1H NMR, 13C NMR and FT-IR spectroscopy, and single-crystal X-ray diffraction. Furthermore, an in-depth assessment of the synthesized compounds was conducted through Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) analysis, in conjunction with docking studies, to elucidate their pharmacokinetic profiles and potential. Impressively, the ADMET analysis showcased encouraging drug-likeness properties of the newly synthesized Schiff bases. These computational findings were substantiated by molecular properties derived from density functional theory (DFT) calculations using the B3LYP/6-31G* method within the Jaguar Module of Schrödinger 2023-2 from Maestro (Schrodinger LLC, New York, USA). The exploration of frontier molecular orbitals (HOMO and LUMO) enabled the computation of global reactivity descriptors (GRDs), encompassing charge separation (Egap) and global softness (S). Notably, within this analysis, one Schiff base, namely, 4-bromo-2-{N-[2-(pyrrolidine-1-sulfonyl)phenyl]carboximidoyl}phenol, 20, emerged with the smallest charge separation (ΔEgap = 3.5780 eV), signifying heightened potential for biological properties. Conversely, 4-bromo-2-{N-[2-(piperidine-1-sulfonyl)phenyl]carboximidoyl}phenol, 17, exhibited the largest charge separation (ΔEgap = 4.9242 eV), implying a relatively lower propensity for biological activity. Moreover, the synthesized Schiff bases displayed remarkeable inhibition of tankyrase poly(ADP-ribose) polymerase enzymes, integral in colon cancer, surpassing the efficacy of a standard drug used for the same purpose. Additionally, their bioavailability scores aligned closely with established medications such as trifluridine and 5-fluorouracil. The exploration of molecular electrostatic potential through colour mapping delved into the electronic behaviour and reactivity tendencies intrinsic to this diverse range of molecules.

Emerging synthetic strategies and pharmacological insights of 1,3,4-thiadiazole derivatives: a comprehensive review

This review meticulously examines the synthesis techniques for 1,3,4-thiadiazole derivatives, focusing on cyclization, condensation reactions and functional group transformations. It enhances the understanding of these chemical methods that re crucial for tailoring derivative properties and functionalities. This study is considered to be vital for researchers, detailing established effects such as antioxidant, antimicrobial and anticancer activities, and revealing emerging pharmacological potentials such as neuroprotective, antiviral and antidiabetic properties. It also discusses the molecular mechanisms underlying these effects. In addition, this article covers structure-activity relationship studies and computational modelling that are essential for designing potent, selective 1,3,4-thiadiazole compounds. This work lays a foundation for future research and targeted therapeutic development.

Telescoping Synthesis of 4-Organyl-5-(organylselanyl)thiazol-2-amines Promoted by Ultrasound

In this work, we describe the synthesis of new 4-organyl-5-(organylselanyl)thiazol-2-amine hybrids through a one-pot two-step protocol. The transition metal-free method involves the use of ultrasound as an alternative energy source and Oxone® as oxidant. To obtain the products, a telescoping approach was used, in which 4-organylthiazol-2-amines were firstly prepared under ultrasonic irradiation, followed by the addition of diorganyl diselenides and Oxone®. Thus, 16 compounds were prepared, with yields ranging from 61 % to 98 %, using 2-bromoacetophenone derivatives and diorganyl diselenides as easily available starting materials.

Shaping the Future of Obesity Treatment: In Silico Multi-Modeling of IP6K1 Inhibitors for Obesity and Metabolic Dysfunction

Recent research has uncovered a promising approach to addressing the growing global health concern of obesity and related disorders. The inhibition of inositol hexakisphosphate kinase 1 (IP6K1) has emerged as a potential therapeutic strategy. This study employs multiple ligand-based in silico modeling techniques to investigate the structural requirements for benzisoxazole derivatives as IP6K1 inhibitors. Firstly, we developed linear 2D Quantitative Structure-Activity Relationship (2D-QSAR) models to ensure both their mechanistic interpretability and predictive accuracy. Then, ligand-based pharmacophore modeling was performed to identify the essential features responsible for the compounds' high activity. To gain insights into the 3D requirements for enhanced potency against the IP6K1 enzyme, we employed multiple alignment techniques to set up 3D-QSAR models. Given the absence of an available X-ray crystal structure for IP6K1, a reliable homology model for the enzyme was developed and structurally validated in order to perform structure-based analyses on the selected dataset compounds. Finally, molecular dynamic simulations, using the docked poses of these compounds, provided further insights. Our findings consistently supported the mechanistic interpretations derived from both ligand-based and structure-based analyses. This study offers valuable guidance on the design of novel IP6K1 inhibitors. Importantly, our work exclusively relies on non-commercial software packages, ensuring accessibility for reproducing the reported models.

Novel cyanochalcones as potential anticancer agents: apoptosis, cell cycle arrest, DNA binding, and molecular docking studies

In the light of anticancer drug discovery and development, a new series of cyanochalcones incorporating indole moiety (5a-g) were efficiently synthesized and characterized by different spectral analysis. MTT assay was used to evaluate the antiproliferative activity of the synthesized compounds towards different cancer cells (Hela, MDA-MB-231, A375, and A549) in parallel with normal cells (HSF). Trimethoxy and diethoxy-containing derivatives (5d and 5e) displayed the most selective cytotoxic activities against cervical Hela cells with IC50 values of 8.29 and 11.82 µM, respectively, with great safety pattern toward normal HSF cells (Selectivity index: 21.3 and 13.9, respectively). Therefore, 5d and 5e were chosen to study their effects on apoptosis, cell cycle arrest, and migration of Hela cells using flow cytometric analysis and wound healing assay. They induced apoptosis and cell cycle arrest at the S phase and impaired migration of HeLa cells. Regarding their effects on the expression profile of crucial genes related to the potential anticancer activities, 5d and 5e remarkably upregulated caspase 3 and Beclin1 and downregulated cyclin A1, CDK2, CDH2, MMP9, and HIF1A using qRT-PCR and ELISA techniques. UV-Vis spectral measurement demonstrated the ability of 5d and 5e to bind CT-DNA efficiently with Kb values of 3.7 × 105 and 1 × 105 M-1, respectively. Moreover, in silico molecular docking was performed to assess the binding affinities of the compounds toward the active sites of Bcl2, CDK2, and DNA. Therefore, cyanochalcones 5d and 5e might be promising anticancer agents and could offer a scientific basis for intensive research into cancer chemotherapy.Communicated by Ramaswamy H. Sarma.

Synthesis and Biological Evaluation of Novel Amino and Amido Substituted Pentacyclic Benzimidazole Derivatives as Antiproliferative Agents

Newly designed pentacyclic benzimidazole derivatives featuring amino or amido side chains were synthesized to assess their in vitro antiproliferative activity. Additionally, we investigated their direct interaction with nucleic acids, aiming to uncover potential mechanisms of biological action. These compounds were prepared using conventional organic synthesis methodologies alongside photochemical and microwave-assisted reactions. Upon synthesis, the newly derived compounds underwent in vitro testing for their antiproliferative effects on various human cancer cell lines. Notably, derivatives 6 and 9 exhibited significant antiproliferative activity within the submicromolar concentration range. The biological activity was strongly influenced by the N atom's position on the quinoline moiety and the position and nature of the side chain on the pentacyclic skeleton. Findings from fluorescence, circular dichroism spectroscopy, and thermal melting assays pointed toward a mixed binding mode-comprising intercalation and the binding of aggregated compounds along the polynucleotide backbone-of these pentacyclic benzimidazoles with DNA and RNA.

Hydrazone Activation in the Aminocatalytic Cascade Reaction for the Synthesis of Tetrahydroindolizines

In this Letter, we demonstrate the usefulness of hydrazone activation for the synthesis of biologically relevant tetrahydroindolizines. A pyrrol-derived hydrazone bearing a Michael acceptor moiety in the N-alkyl side chain has been designed with the aim of participating in the aminocatalytic cascade reaction leading to the annulation of the new six-membered heterocyclic scaffold. The application of (S)-(-)-α,α-diphenyl-2-pyrrolidinemethanol trimethylsilyl ether as the aminocatalyst allows for the iminium ion-enamine-mediated cascade to proceed in a fully stereoselective manner.

Cytotoxicity Activity of Some meso-Dihydroguaiaretic Acid Derivatives and Mode of Action of the Most Active Compound

The aim of this study was to screen sixteen meso-1 semi-synthetic derivatives bearing ether, esther, carbamate, phosphate or aminoether functional groups against five cancer cell lines: MCF-7 (breast), A549 (lung), HepG2 (liver), HeLa (cervix), and DU145 (prostate) at 25 μM using the MTT assay. Results from the screening showed that two derivatives had the lowest percentage of cell viability at 25 μM, the aminoether derivative meso-11 and the esther derivative meso-20 against A549 (44.15±0.78 %) and MCF-7 (41.60±0.92 %), respectively. Then, it was determined the IC50 value of each compound against their most sensitive cancer cell line. Results showed that aminoether derivative meso-11 showed potent cytotoxicity against A549 (IC50 =17.11±2.11 μM), whereas it resulted more cytotoxic against the LL-47 lung normal cell line (IC50 =9.49±1.19 μM) having a Selective Index (SI) of 0.55. On the other hand, the esther derivative meso-20 exhibited potent activity against MCF-7 (IC50 =18.20±1.98 μM), whereas it displayed moderate cytotoxicity against the MCF-10 breast normal cell line (IC50 =41.22±2.17 μM) with a SI of 2.2. Finally, studies on the mechanism of action of meso-20 indicated disruption of MCF-7 plasma membrane in vitro and the AMPK activation in silico.

Recent drug design strategies and identification of key heterocyclic scaffolds for promising anticancer targets

Cancer, a noncommunicable disease, is the leading cause of mortality worldwide and is anticipated to rise by 75% in the next two decades, reaching approximately 25 million cases. Traditional cancer treatments, such as radiotherapy and surgery, have shown limited success in reducing cancer incidence. As a result, the focus of cancer chemotherapy has switched to the development of novel small molecule antitumor agents as an alternate strategy for combating and managing cancer rates. Heterocyclic compounds are such agents that bind to specific residues in target proteins, inhibiting their function and potentially providing cancer treatment. This review focuses on privileged heterocyclic pharmacophores with potent activity against carbonic anhydrases and kinases, which are important anticancer targets. Evaluation of ongoing pre-clinical and clinical research of heterocyclic compounds with potential therapeutic value against a variety of malignancies as well as the provision of a concise summary of the role of heterocyclic scaffolds in various chemotherapy protocols have also been discussed. The main objective of the article is to highlight key heterocyclic scaffolds involved in recent anticancer drug design that demands further attention from the drug development community to find more effective and safer targeted small-molecule anticancer agents.

Synthesis, photophysical properties, anticancer evaluation, and molecular docking studies of new pyrimidine linked 4-arylidene-thiazolidin-4-ones as potent anticancer agents

The reaction of 4-(chloroacetamido)pyrimidine (1) with ammonium thiocyanate gave 2-(pyrimidin-4-ylimino)thiazolidin-4-one (2), which, when condensed with four substituted benzaldehyde analogues, gave the consequent 5-arylidine-2-(pyrimidin-4-ylimino)thiazolidin-4-ones 3a-d. In addition, the absorbance and fluorescence behaviours of pyrimidinylimino-thiazolidin-4-one hybrids 3a-d in various organic solvents were investigated. The emphasis was on studying UV absorption capacities and the effect of various structural components on photophysical qualities such as the 5-arylidene-2-(pyrimidin-4-ylimino)thiazolidin-4-ones and N,N-dimethylamino tail. The cytotoxic effect of four pyrimidinylimino-thiazolidin-4-one hybrids 3a-d on tumour cell lines (HepG2, HCT-116, PC3, MCF-7) and a normal cell line (WI38) is investigated in this work. The cytotoxicity was measured by comparing the half-maximal inhibitory concentration (IC50 ) to the reference medication, 5-fluorouracil. The findings indicate that these hybrid compounds had varying cytotoxic effects on the cell lines examined; hybrids 3b and 3c demonstrated significant anticancer activity against MCF-7 with IC50 values of 7.53 ± 0.43 and 9.17 ± 0.31 μM, respectively. The inhibitory efficacy of various synthesized hybrids on the epidermal growth factor receptor (EGFR) kinase was investigated. EGFR is a crucial target in cancer treatment because inhibiting it may reduce tumour development and proliferation. The IC50 value was used to calculate the inhibitory activity, which is the concentration of inhibitor necessary to induce half-maximal inhibition of EGFR kinase activity. In addition, the predicted ADME results show that pyrimidinylimino-thiazolidin-4-one hybrids have good pharmacokinetic properties; hybrid 3d is more lipophilic than the other compounds. It has a medium molecular weight, a small number of hydrogen bond acceptors and donors, and a large number of aromatic heavy atoms. Moreover, molecular docking simulations revealed precise information on the interactions of pyrimidinylimino-thiazolidin-4-one hybrids 3a-d and 5-Fu with their respective protein targets. These interactions point to possible pathways for their biological activities and call for more testing to establish their effectiveness as bioactive molecules or therapeutic candidates.

Syntheses and Cytotoxicities of Quinazolinone-Based Conjugates

Two novel series of quinazolinone-based hybrids, including quinazolinone-1,3,4-oxadiazoles (10a-l) and quinazolinone-1,3,4-oxadiazole-benzimidazoles (8a-e), were designed and synthesized and their cytotoxic activities against three human cancer cell lines, lung cancer (A549), cervical cancer (HeLa), and breast cancer (MCF-7), were evaluated. The cytotoxic assays revealed that 10i with a lipophilic 4-fluoro-phenyl moiety at the C-2 position of the quinazolinone ring displayed good cytotoxicities against the A549 and MCF-7 cell lines, while 8b-d with the thioether-linked benzimidazole moiety incorporated on the right side of the oxadiazole ring induced comparable stronger activities toward the MCF-7 cell line, relative to the simple two-heterocycle-containing hybrid 10i. These novel quinazolinone-based hybrids could be considered as lead compounds that merit further optimization and development as anti-cancer agents.

Computational Exploration of Fluorocyclopentenyl-purines and-pyrimidines Derivatives as Potential Inhibitors of Epidermal Growth Factor Receptor (EGFR) for the Treatment of Breast Cancer

The Epidermal Growth Factor Receptor (EGFR) is an important therapeutic target for the treatment of a variety of epithelial malignancies, including breast cancer, in which EGFR is aberrantly expressed.The fluorocyclopentenyl-purine-pyrimidines derivatives, which have previously been described as powerful compounds against breast cancer, were selected to investigate their potential against EGFR using computational tools in an effort to obtain potent inhibitors with fewer adverse effects. The molecule's chemical reactivity and stability were assessed by determining the HOMO-LUMO energy gap using density functional theory (DFT) calculations. Among all the selected compounds, PU4 displayed a HOMO-LUMO gap of 0.191 eV. Additionally, molecular docking analysis was performed to assess the binding affinities of PU4 within the active pocket of EGFR-TK. The compound PU4 showed potent interactions with EGFR exhibiting -32.3 kJ/mol binding energy which was found best as compared to gefitinib i. e., -27.4 kJ/mol which was further validated by molecular dynamics simulations and ADMET analysis. The results of these analyses indicate that the top hits obtained from the virtual screening possess the ability to act as effective EGFR inhibitor. Therefore, it is recommended to further investigate the inhibitory potential of these identified compounds using in vitro and in vivo approaches.

Exploring cyclin-dependent kinase inhibitors: a comprehensive study in search of CDK-6 inhibitors using a pharmacophore modelling and dynamics approach

Cancer prevalence and resistance issues in cancer treatment are a significant public health concern globally. Among the existing strategies in cancer therapy, targeting cyclin-dependent kinases (CDKs), especially CDK-6 is found to be one of the most promising targets, as this enzyme plays a pivotal role in cell cycle stages and cell proliferation. Cell proliferation is the characteristic feature of cancer giving rise to solid tumours. Our research focuses on creating novel compounds, specifically, pyrazolopyrimidine fused azetidinones, using a groundbreaking molecular hybridization approach to target CDK-6. Through computational investigations, ligand-based pharmacophore modelling, pharmacokinetic studies (ADMET), molecular docking, and dynamics simulations, we identified 18 promising compounds. The pharmacophore model featured one aromatic hydrophobic centre (F1: Aro/Hyd) and two H-bond acceptors (F2 and F3: Acc). Molecular docking results showed favourable binding energies (-6.5 to -8.0 kcal mol-1) and effective hydrogen bonds and hydrophobic interactions. The designed compounds demonstrated good ADMET profiles. Specifically, B6 and B18 showed low energy conformation (-7.8 kcal and -7.6 kcal), providing insights into target inhibition compared to the standard drug Palbociclib. Extensive molecular dynamics simulations confirmed the stability of these derivatives. Throughout the 100 ns simulation, the ligand-protein complexes maintained structural stability, with acceptable RMSD values. These compounds hold promise as potential leads in cancer therapy.

Novel 1,2,3-Triazole-Containing Quinoline-Benzimidazole Hybrids: Synthesis, Antiproliferative Activity, In Silico ADME Predictions, and Docking

The newly synthesized quinoline-benzimidazole hybrids containing two types of triazole-methyl-phenoxy linkers were characterized via NMR and elemental analysis. Additional derivatization was achieved by introducing bromine at the C-2 position of the phenoxy core. These novel hybrids were tested for their effects on the growth of the non-tumor cell line MRC-5 (human fetal lung fibroblasts), leukemia and lymphoma cell lines: Hut78, THP-1 and HL-60, and carcinoma cell lines: HeLa and CaCo-2. The results obtained, presented as the concentration that achieves 50% inhibition of cell growth (IC50 value), show that the compounds tested affect tumor cell growth differently depending on the cell line and the dose applied (IC50 ranged from 0.2 to >100 µM). The quinoline-benzimidazole hybrids tested, including 7-chloro-4-(4-{[4-(5-methoxy-1H-1,3-benzo[d]imidazol-2-yl)phenoxy]methyl}-1H-1,2,3-triazol-1-yl)quinoline 9c, 2-(3-bromo-4-{[1-(7-chloroquinolin-4-yl)-1H-1,2,3-triazol-4-yl]methoxy}phenyl)-N-propyl-1H-benzo[d]imidazol-5-carboximidamide trihydrochloride 10e, 2-{4-[(1-{2-[(7-chloroquinolin-4-yl)amino]ethyl}-1H-1,2,3-triazol-4-yl)methoxy]phenyl}-N-propyl-1H-benzo[d]imidazol-5-carboximidamide trihydrochloride 14e and 2-{3-bromo-4-[(1-{2-[(7-chloroquinolin-4-yl)amino]ethyl}-1H-1,2,3-triazol-4-yl)methoxy]phenyl}-N-propyl-1H-benzo[d]imidazol-5-carboximidamide trihydrochloride 15e, arrested the cell cycle of lymphoma (HuT78) cells. The calculated ADMET properties showed that the synthesized compounds violated at most two of Lipinski's rules, making them potential drug candidates, but mainly for parenteral use due to low gastrointestinal absorption. The quinoline-benzimidazole hybrid 14e, which was shown to be a potent and selective inhibitor of lymphoma cell line growth, obtained the highest binding energy (-140.44 kcal/mol), by docking to the TAO2 kinase domain (PDB: 2GCD).

Reliable and accurate prediction of basic pK[Formula: see text] values in nitrogen compounds: the pK[Formula: see text] shift in supramolecular systems as a case study

This article presents a quantitative structure-activity relationship (QSAR) approach for predicting the acid dissociation constant (pK[Formula: see text]) of nitrogenous compounds, including those within supramolecular complexes based on cucurbiturils. The model combines low-cost quantum mechanical calculations with QSAR methodology and linear regressions to achieve accurate predictions for a broad range of nitrogen-containing compounds. The model was developed using a diverse dataset of 130 nitrogenous compounds and exhibits excellent predictive performance, with a high coefficient of determination (R[Formula: see text]) of 0.9905, low standard error (s) of 0.3066, and high Fisher statistic (F) of 2142. The model outperforms existing methods, such as Chemaxon software and previous studies, in terms of accuracy and its ability to handle heterogeneous datasets. External validation on pharmaceutical ingredients, dyes, and supramolecular complexes based on cucurbiturils confirms the reliability of the model. To enhance usability, a script-like tool has been developed, providing a streamlined process for users to access the model. This study represents a significant advancement in pK[Formula: see text] prediction, offering valuable insights for drug design and supramolecular system optimization.

Antiproliferative and Tubulin-Destabilising Effects of 3-(Prop-1-en-2-yl)azetidin-2-Ones and Related Compounds in MCF-7 and MDA-MB-231 Breast Cancer Cells

A series of novel 3-(prop-1-en-2-yl)azetidin-2-one, 3-allylazetidin-2-one and 3-(buta-1,3-dien-1-yl)azetidin-2-one analogues of combretastatin A-4 (CA-4) were designed and synthesised as colchicine-binding site inhibitors (CBSI) in which the ethylene bridge of CA-4 was replaced with a β-lactam (2-azetidinone) scaffold. These compounds, together with related prodrugs, were evaluated for their antiproliferative activity, cell cycle effects and ability to inhibit tubulin assembly. The compounds demonstrated significant in vitro antiproliferative activities in MCF-7 breast cancer cells, particularly for compounds 9h, 9q, 9r, 10p, 10r and 11h, with IC₅₀ values in the range 10-33 nM. These compounds were also potent in the triple-negative breast cancer (TBNC) cell line MDA-MB-231, with IC₅₀ values in the range 23-33 nM, and were comparable with the activity of CA-4. The compounds inhibited the polymerisation of tubulin in vitro, with significant reduction in tubulin polymerization, and were shown to interact at the colchicine-binding site on tubulin. Flow cytometry demonstrated that compound 9q arrested MCF-7 cells in the G₂/M phase and resulted in cellular apoptosis. The antimitotic properties of 9q in MCF-7 human breast cancer cells were also evaluated, and the effect on the organization of microtubules in the cells after treatment with compound 9q was observed using confocal microscopy. The immunofluorescence results confirm that β-lactam 9q is targeting tubulin and resulted in mitotic catastrophe in MCF-7 cells. In silico molecular docking supports the hypothesis that the compounds interact with the colchicine-binding domain of tubulin. Compound 9q is a novel potent microtubule-destabilising agent with potential as a promising lead compound for the development of new antitumour agents.

Antioxidant activity of novel nitrogen scaffold with docking investigation and correlation of DFT stimulation

Heterocyclic scaffolds are frequently employed in drug development to treat a variety of conditions, including cancers. These substances have the ability to engage covalently or non-covalently with particular residues in the target proteins, inhibiting them. In this study, the formation of N-, S-, and O-containing heterocycles by the interaction of chalcone with nitrogen-containing nucleophiles such as hydrazine, hydroxyl amine, guanidine, urea, and aminothiourea was explored. FT-IR, UV-visible, NMR, and mass spectrometric studies were used to confirm the heterocyclic compounds that were produced. These substances were tested for their antioxidant activity by their capacity to scavenge the artificial radicals 2,2-diphenyl-1-picrylhydrazyl (DPPH). The strongest antioxidant activity was demonstrated by compound 3 (IC₅₀ = 93.4 μM), whereas compound 8 (IC₅₀ = 448.70 μM) had the lowest activity when compared to vitamin C (IC₅₀ 141.9 μM). Also, the experimental findings and the docking estimation of these heterocyclic compounds with PDBID:3RP8 were in agreement. Additionally, the compounds' global reactivity characteristics, such as HOMO-LUMO gaps, electronic hardness, chemical potential, electrophilicity index, and Mulliken charges, were identified using DFT/B3LYP/6-31G(d,p) basis sets. The two chemicals that displayed the best antioxidant activity also had their molecular electrostatic potential (MEP) ascertained using DFT simulations.

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.