Design, synthesis and biological evaluation of new 4-(4-substituted-anilino)quinoline derivatives as anticancer agents

Molecular Docking, Pharmacokinetic and Molecular Simulation Analysis of Novel Mono-Carbonyl Curcumin Analogs as L858R/T790M/C797S Mutant EGFR Inhibitors

INTRODUCTION

Curcumin, an anticancer natural compound with multiple pharmacological activities, has a weak pharmacokinetic and instability due to diketone moiety. Curcumin's stability challenges can be overcome by removing the diketone moiety and shortening the 7-carbon chain, resulting in mono-carbonyl analogs. Cancer proliferation is caused by the activation of Epidermal Growth Factor (EGFR) pathways. Current available EGFR inhibitors have an issue of resistance.

AIM

Thus, we aimed to design new mono-carbonyl curcumin derivatives and analyse their drug likeness properties. Further, to investigate them on three distinct crystal structures, namely two wild-type and L858R/T790M/C797S mutant generations for EGFR inhibitory activity.

METHOD

Ten New Molecular Entities (NME's) were designed using literature survey. These molecules were subjected to comparative molecular docking, on the EGFR crystal structures viz. wild-type (PDB: 1M17 and 4I23) and L858R/T790M/C797S mutant (PDB: 6LUD) using Schrodinger software. The molecules were also tested for Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) properties. The docked complex of the hit molecule was studied for molecular simulation.

RESULT AND DISCUSSION

In molecular docking studies, NMEs 1, 2, and 3 were found to have good binding affinity with 1st , 2nd , and 3rd generation EGFR crystal structures and a greater dock score than standard curcumin. All molecules have shown a good ADMET profile. Since L858R/T790M/C797S is currently being explored more, we decided to take the best molecule, NME 3, for molecular dynamics with 6LUD, and the results were compared with those of the co-crystallized ligand S4 (Osimertinib). It was found that the Relative mean square standard deviation (RMSD) (1.8 Å), Relative mean standard Fluctuation (RMSF) (1.45 Å) and radius of gyration (4.87 Å) values of NME 3 were much lower than those of reference S4. All these confirm that our designed NME 3 is more stable than reference S4.

CONCLUSION

NME 1 and NME 2 have shown better binding against wild type of EGFR. NME 3 have shown comparable binding and more stability as compared to Osimertinib against L858R/T790M/C797S mutated protein structure. The hit compound can be further explored for its Molecular mechanics with generalised Born and surface area solvation (MM-GBSA) and discrete Fourier transform (DFT) studies to find out the energy and atomic level study. In the future, this molecule could be taken for wet lab studies and can be tested for mutated EGFR inhibitory activity.

Novel Para-Aminobenzoic Acid Analogs and Their Potential Therapeutic Applications

A "building block" is a key component that plays a substantial and critical function in the pharmaceutical research and development industry. Given its structural versatility and ability to undergo substitutions at both the amino and carboxyl groups, para-aminobenzoic acid (PABA) is a commonly used building block in pharmaceuticals. Therefore, it is great for the development of a wide range of novel molecules with potential medical applications. Anticancer, anti-Alzheimer's, antibacterial, antiviral, antioxidant, and anti-inflammatory properties have been observed in PABA compounds, suggesting their potential as therapeutic agents in future clinical trials. PABA-based therapeutic chemicals as molecular targets and their usage in biological processes are the primary focus of this review study. PABA's unique features make it a strong candidate for inclusion in a massive chemical database of molecules having drug-like effects. Based on the current literature, further investigation is needed to evaluate the safety and efficacy of PABA derivatives in clinical investigations and better understand the specific mechanism of action revealed by these compounds.

Phthalazone tethered 1,2,3-triazole conjugates: In silico molecular docking studies, synthesis, in vitro antiproliferative, and kinase inhibitory activities

New phthalazone tethered 1,2,3-triazole derivatives 12-21 were synthesized utilizing the Cu(I)-catalyzed click reactions of alkyne-functionalized phthalazone 1 with functionalized azides 2-11. The new phthalazone-1,2,3-triazoles structures 12-21 were confirmed by different spectroscopic tools, like IR; 1H, 13C, 2D HMBC and 2D ROESY NMR; EI MS, and elemental analysis. The antiproliferative efficacy of the molecular hybrids 12-21 against four cancer cell lines was evaluated, including colorectal cancer, hepatoblastoma, prostate cancer, breast adenocarcinoma, and the normal cell line WI38. The antiproliferative assessment of derivatives 12-21 showed potent activity of compounds 16, 18, and 21 compared to the anticancer drug doxorubicin. Compound 16 showed selectivity (SI) towardthe tested cell lines ranging from 3.35 to 8.84 when compared to Dox., that showed SI ranged from 0.75 to 1.61. Derivatives 16, 18 and 21 were assessed towards VEGFR-2 inhibitory activity and result in that derivative 16 showed the potent activity (IC50 = 0.123 µM) in comparison with sorafenib (IC50 = 0.116 µM). Compound 16 caused an interference with the cell cycle distribution of MCF7 and increased the percentage of cells in S phase by 1.37-fold. In silico molecular docking of the effective derivatives 16, 18, and 21 against vascular endothelial growth factor receptor-2 (VEGFR-2) confirmed the formation of stable protein-ligand interactions within the pocket.

Molecular dynamic simulations based discovery and development of thiazolidin-4-one derivatives as EGFR inhibitors targeting resistance in non-small cell lung cancer (NSCLC)

Targeting kinases with oncogenic driver mutations in malignancies with allosteric kinase inhibitors is a promising new treatment technique. EGFR inhibitors targeting the L858R/T790M/C797S mutation bearing thiazolidine-4-one scaffold were discovered, optimized, synthesized, and biologically evaluated. According to in silico and in vitro studies, compounds 6a and 6b resulted to be highly potent with IC₅₀ values of 120 nM and 134 nM and good selectivity. Compound 6a displayed significant antioxidant activity, with a DPPH radical scavenging value of 92.15%. The potency of compounds was also compared with ADMET and molecular dynamics simulations study. A comparative simulation of model protein and protein-ligand complex in presence and absence of compound 6a has been carried out. Communicated by Ramaswamy H. Sarma.

Characterization of novel heterocyclic compounds based on 4-aryl-4H-chromene scaffold as anticancer agents: Design, synthesis, antiprofilerative activity against resistant cancer cells, dual β-tubulin/c-Src inhibition, cell cycle arrest and apoptosis induction

In this study, three novel sets of 4-aryl-4H-chromene derivatives 4a-c, 6a-d and 7a-c were synthesized and evaluated for anticancer activity. Characterization of new compounds was established on basis of elemental analyses and spectral data. All new compounds were investigated for their antiproliferative activity against HCT-116, HepG-2 and MCF-7 cell lines using vinblastine and staurosporine as positive controls. Compounds 4b, 4c and 6d showed superior cytotoxicity against HCT-116, HepG-2 and MCF-7 cell lines, respectively with IC₅₀ ranged from 3.31 to 4.95 μM. Additionally, compound 4b showed excellent cytotoxic activity (IC₅₀ = 39.83 μM) against resistant HCT-116 better than doxorubicin (IC₅₀ = 164.60 μM), while compounds 4c and 6d exhibited moderate cytotoxic activity against resistant HepG-2 and resistant MCF-7 cell lines. The most potent compounds inhibited both β-tubulin polymerization (IC₅₀ = 8.78 - 16.47 μM) and c-Src kinase (IC₅₀ = 0.07 - 0.18 μM) enzymes. Compounds 4b, 4c and 6d activated caspase-3, caspase-7, and caspase-9 proteins relative to untreated cells, revealing apoptosis induction. Apoptosis was also confirmed through up-regulation of Bax and down-regulation of Bcl-2 protein expression levels. Cell cycle analysis of compound 6d showed accumulation of cells in pre-G1 phase and cell cycle arrest at S phase in MCF-7 treated cells. As well 6d caused 7- and 63- fold increase in apoptotic cell population at early and late apoptosis stages. Finally, molecular modeling study was performed to predict the binding pattern of the target compounds inside c-Src kinase receptor.

Quinoline-based thiazolidinone derivatives as potent cytotoxic and apoptosis-inducing agents through EGFR inhibition

Quinoline-based thiazolidinone heterocycles exhibited potent activity in the field of cancer therapy. Hence, ten quinoline-based thiazolidinone derivatives were evaluated for their anticancer activity through cytotoxic activity, epidermal growth factor receptor (EGFR) inhibition pathway, apoptosis investigation through flow cytometric analyses, RT-PCR gene expression, in vivo solid-Ehrlich carcinoma model, and finally in silico approach for highlighting the interaction pose. Results revealed that compound 7 exhibited cytotoxic activity against HCT-116 cells with an IC₅₀ value of 7.43 µM compared to 5-FU (IC₅₀  = 11.36 µM) with moderate cytotoxic activity against the FHC (IC₅₀  = 35.27 µM), and it exhibited remarkable inhibition activity of EGFR with IC₅₀ value of 96.43 nM compared to Erlotinib (IC₅₀  = 78.65 nM). Moreover, it significantly stimulated apoptotic colon cancer cell death with 171.58-fold arresting cell cycle at G2 and S-phases. Additionally, it ameliorated both biochemical and histochemical structures near normal with tumor inhibition ratio of 52.92% compared to 5-FU of 57.16%, with immunohistochemical examinations of EGFR inhibition in the treated group compared to control. Finally, molecular docking study highlighted its good binding affinity through good interactive binding pose inside the EGFR protein. In conclusion, the potent EGFR inhibitory activity of compound 7 was investigated using three integrated approaches in vitro, in vivo, and in silico, so it worth be validated and developed as a chemotherapeutic anticancer agent.

Antitumor Activities for Two Pt(II) Complexes of Tropolone and 8-Hydroxyquinoline Derivative

The reactions of cis-Pt(DMSO)₂Cl₂ and tropolone (HL) with 8-hydroxyquinoline (HQ) or 2-methyl-8-hydroxyquinoline (HMQ) gave [Pt(Q)(L)] (1) and [Pt(MQ)(L)] (2), which present mononuclear structures with their Pt(II) ions four-coordinated in square planar geometries. Their in vitro biological properties were evaluated by MTT assay, which showed a remarkable cytotoxic activity on the cancer cell lines. 1 shows higher cytotoxic activities on tumor cells such as T24, HeLa, A549, and NCI-H460 than complex 2 and cisplatin, with IC₅₀ values <16 μM. Among them, an IC₅₀ value of 3.6 ± 0.63 μM was found for complex 1 against T24 cells. It presented a tuning cytotoxic activity by substitution groups on 8-hydroxyquinoline skeleton. In our case, the substitution groups of -H are much superior to -CH₃ against tumor cells. It revealed that both complexes can induce cell apoptosis by decreasing the potential of a mitochondrial membrane, enhancing reactive oxygen species and increasing Ca²⁺ levels of T24 cells. The T24 cell cycle can be arrested at G2 and G1 phases by complexes 1 and 2, respectively, with an upregulation for P21 and P27 expression levels and a down-regulation for cyclin A, CDK1, Cdc25A, and cyclin B expression levels. Furthermore, complex 1 exhibits satisfactory in vivo antitumor activity as revealed by the tumor inhibitory rate and the tumor weight change as well as by the cute toxicity assay and renal pathological examinations, which is close to cisplatin and much better than complex 2. All of these suggest that 1 might be a potential candidate for developing into a safe and effective anticancer agent.

Free energy perturbation guided Synthesis with Biological Evaluation of Substituted Quinoline derivatives as small molecule L858R/T790M/C797S mutant EGFR inhibitors targeting resistance in Non-Small Cell Lung Cancer (NSCLC)

Two different schemes of novel substituted quinoline derivatives were designed and synthesized via simple reaction steps and conditions. A comparative molecular docking study was carried out on two different types of EGFR enzymes which include wild-type (PDB: 4I23) and T790M mutated (PDB: 2JIV) respectively. Compounds were also validated upon T790M/C797S mutated (PDB ID: 5D41) EGFR enzyme at the allosteric binding site. Free energy perturbations were carried out to determine the absolute binding free energy of a protein-ligand complex in the form of ΔG_binding, which in turn provided 4ab and 5ad as the most potential contenders through the structural enhancement in the determined initial scaffolds. Anticancer activity of the synthesized derivatives was examined against HCC827, H1975 (L858R/T790M), A549, and HT-29 cell lines by standard MTT assay. Compound 4ad (6-chloro-2-(isoindolin-2-yl)-4-methylquinoline) has shown excellent inhibitory activities against mutant EGFR kinase with IC₅₀ value 0.91 µM. The potency of compounds 4ab, 4ad and 5adwas compared throughan insilicoADMET study.

New Benzoxazole Derivatives as Antiprotozoal Agents: In Silico Studies, Synthesis, and Biological Evaluation

Background. Benzoxazole derivatives have different biological activities. In pursuit of designing novel chemical entities with antiprotozoal and antimicrobial activities, benzoxazolyl aniline was utilized as a privileged scaffold of a series of (3-benzoxazole-2-yl) phenylamine derivatives, 3-benzoxazoloyl acetamide, and butyramide derivatives. Methods. These novel analogs were synthesized in straightforward simple chemistry without any quantitative chromatographic separations in reasonable yields. The biological evaluation of all target compounds as potential antimalarial, antileishmanial, antitrypanosomal, and antimicrobial agents was performed by various well-established cell-based methods. Results. Compounds 6d and 5a showed promising biological screening data. The amidation of 3-benzoxazolyl aniline 1 with the chloroacetyl functional group resulted in a good antimalarial activity and showed moderate inhibitory activities against leishmanial and trypanosomal spp. Moreover, chloroacetyl functionalization of benzoxazolyl aniline serves as a good early goal for constructing and synthesizing new antimicrobial and antiprotozoal agents. The molecular docking study rationalizes the relative inhibitory activity of compound 5a as an antimalarial agent with the deregulation of PfPNP activity which has emerged as a major mechanism of these targets.

Computational and Synthetic approach with Biological Evaluation of Substituted Quinoline derivatives as small molecule L858R/T790M/C797S triple mutant EGFR inhibitors targeting resistance in Non-Small Cell Lung Cancer (NSCLC)

New substituted quinoline derivatives were designed and synthesized via a five-step modified Suzuki coupling reaction. A comparative molecular docking study was carried out on two different types of EGFR enzymes which include wild-type (PDB: 4I23) and T790M mutated (PDB: 2JIV) respectively. Compounds were also validated upon T790M/C797S mutated (PDB ID: 5D41) EGFR enzyme at the allosteric binding site. All docking studies confirmed high potency and flexibility towards wild type as well as a mutated enzyme. Anticancer activity of the synthesized derivatives was examined against HCC827, H1975 (L858R/T790M/C797S and L858R/T790M), A549, and HT-29 cell lines by standard MTT assay. Most of the quinoline derivatives revealed a significant cytotoxic effect. The IC50 values of 4-(4-methylquinolin-2-yl)phenyl 4-(chloromethyl)benzoate (5j) were found to be 0.0042 µM, 0.02 µM, 1.91 µM, 3.82 µM and 3.67 µM while IC50 values of osimertinib were 0.0040 µM, 0.02 µM, ND, 0.99 µM and 1.22 µM, respectively. Compound 5j has shownexcellent inhibitory activities against EGFR kinases triple mutant with IC 50 value 1.91 µM. It was observed that, compared to H1975, A549 and A431 cell lines, synthesized compounds significantly inhibited proliferation of the HCC827 cell line. These data suggested that synthesized compounds showed promising selective anticancer activity against tumor cells harboring EGFR Del E746-A750. The potency of compound 5j was compared through molecular dynamic simulations andan insilicoADMET study. QSAR models were generated and the best model was correctly compared with respect to predicted and observed activity of compounds. The built model will assist to design, refine and construct novel substituted quinoline derivatives as potent EGFR inhibitors in near future.

Recent Advances in the Synthesis and Biological Activity of 8-Hydroxyquinolines

Compounds containing the 8-hydroxyquinoline (8-HQ) 1 nucleus exhibit a wide range of biological activities, including antimicrobial, anticancer, and antifungal effects. The chemistry and biology of this group have attracted the attention of chemists, medicinal chemists, and professionals in health sciences. A number of prescribed drugs incorporate this group, and numerous 8-HQ- based molecules can be used to develop potent lead compounds with good efficacy and low toxicity. This review focusses on the recent advances in the synthesis of 8-HQ derivatives with different pharmacological properties, including anticancer, antiviral, and antibacterial activities. For this purpose, recent relevant references were searched in different known databases and search engines, such as MEDLINE (PubMed), Google Scholar, Science Direct, Scopus, Cochrane, Scientific Information Database (SID), SciFinder, and Institute for Scientific Information (ISI) Web of Knowledge. This review article provides a literature overview of the various synthetic strategies and biological activities of 8-HQ derivatives and covers the recent related literature. Taken together, compounds containing the 8-HQ moiety have huge therapeutic value and can act as potential building blocks for various pharmacologically active scaffolds. In addition, several described compounds in this review could act leads for the development of drugs against numerous diseases including cancer.

Design and Synthesis of 4(1H)-quinolone Derivatives as Autophagy Inducing Agents by Targeting ATG5 Protein

Background:

Quinolines have been characterized as a class of potential antitumor agents, and a large number of natural and synthetic quinolines acting as antitumor agents were reported.

Methods:

A series of 7-chloro-4(1H)-quinolone derivatives were synthesized. The antiproliferative effect of these compounds was evaluated by MTT assay against five human tumor cell lines. The mechanism of action of the selected compound 7h was also investigated.

Results and Discussion:

Most of the compounds had more potent antiproliferative activities than the lead compound 7-chloro-4(1H)-quinolone 6b. Compound 7h was found to be the most potent antiproliferative agent against human tumor cell lines. Further investigation demonstrated that compound 7h triggered ATG5-dependent autophagy of colorectal cancer cells by promoting the functions of LC3 proteins.

Conclusion:

These results were useful for designing and discovering more potent novel antitumor agents endowed with better pharmacological profiles.

Sulfonamide-based 4-anilinoquinoline derivatives as novel dual Aurora kinase (AURKA/B) inhibitors: Synthesis, biological evaluation and in silico insights

Aurora kinases (AURKs) were identified as promising druggable targets for targeted cancer therapy. Aiming at the development of novel chemotype of dual AURKA/B inhibitors, herein we report the design and synthesis of three series of 4-anilinoquinoline derivatives bearing a sulfonamide moiety (5a-d, 9a-d and 11a-d). The % inhibition of AURKA/B was determined for all target quinolines, then compounds showed more than 50% inhibition on either of the enzymes, were evaluated further for their IC₅₀ on the corresponding enzyme. In particular, compound 9d displayed potent AURKA/B inhibitory activities with IC₅₀ of 0.93 and 0.09 µM, respectively. Also, 9d emerged as the most efficient anti-proliferative analogue in the US-NCI anticancer assay toward the NCI 60 cell lines panel, with broad spectrum activity against different cell lines from diverse cancer subpanels. Docking studies, confirmed that, the sulfonamide SO₂ oxygen was involved in a hydrogen bond with Lys162 and Lys122 in AURKA and AURKB, respectively, whereas, the sulfonamide NH could catch hydrogen bond interaction with the surrounding amino acid residues Lys141, Glu260, and Asn261 in AURKA and Lys101, Glu177, and Asp234 in AURKB. Furthermore, N1 nitrogen of the quinoline scaffold formed an essential hydrogen bond with the hinge region key amino acids Ala213 and Ala173 in AURKA and AURKB, respectively.

Low-dimensional compounds containing bioactive ligands. Part XIV: High selective antiproliferative activity of tris(5-chloro-8-quinolinolato)gallium(III) complex against human cancer cell lines

Four gallium(III) complexes, [Ga(ClQ)₃]⋅MeOH (1 - MeOH), [Ga(ClQ)₃] (1), [Ga(BrQ)₃] (2), [Ga(dIQ)₃] (3) and [Ga(CQ)₃] (4), were prepared (H-ClQ = 5-chloro-8-quinolinol, H-BrQ = 7-bromo-8-quinolinol, H-dIQ = 5,7-diiodo-8-quinolinol, H-CQ = 5-chloro-7-iodo-8-quinolinol) and characterised by elemental analysis, IR and NMR spectroscopy. Single crystal structure analysis of 1 - MeOH confirmed that the complex has a molecular structure with gallium(III) metal ion coordinated in mer-fashion by N- and O-donor atoms of three ClQ ligands. Stability of all complexes in DMSO was proved by ¹H NMR spectroscopy. The in vitro antiproliferative activity of 1 was evaluated against the A2780, MBA-MB-231 and HCT116 cell lines. Complex 1 displays higher antiproliferative activity (IC₅₀ values in the range 2.1-6 μm) compared to the ClQ ligand and cisplatin; and a significant selective antiproliferative potency (IC₅₀ = 136 μm, for normal MRC5pd30 cell line). Radical scavenging experiments revealed that complex 1 exhibits the highest antioxidant activity of the prepared complexes as well as the ligands.

High in vitro and in vivo antitumor activities of Ln(III) complexes with mixed 5,7-dichloro-2-methyl-8-quinolinol and 4,4'-dimethyl-2,2'-bipyridyl chelating ligands

Three novel Ln(III) complexes, namely, [Pm(dmbpy)(ClQ)₂NO₃] (1), [Yb(dmbpy)(ClQ)₂NO₃] (2), and [Lu(dmbpy)(ClQ)₂NO₃] (3), with mixed 5,7-dichloro-2-methyl-8-quinolinol (H-ClQ) and 4,4'-dimethyl-2,2'-bipyridyl (dmbpy) chelating ligands were first synthesized. The cytotoxic activity of Ln(III) complexes 1-3, H-ClQ, and dmbpy against a panel of human normal and cancer cell lines, namely, human non-small cell lung cancer cells (NCI-H460), human cervical adenocarcinoma cancer cells, human ovarian cancer cells, and human normal hepatocyte cells, were evaluated by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. The three novel Ln(III) complexes showed a high in vitro antitumor activity toward the NCI-H460 with IC₅₀ of 1.00 ± 0.25 nM for 1, 5.13 ± 0.44 μM for 2, and 11.87 ± 0.79 μM for 3, respectively. In addition, Ln(III) complexes 1 and 2 exerted their in vitro antitumor activity/mechanism mainly via the mitochondrial death pathway and caused a G2/M phase arrest in the following order: 1 > 2. An NCI-H460 tumor xenograft mouse model was used to evaluate the Pm(III) complex 1in vivo antitumor activity. Pm(III) complex 1 showed a high in vivo antitumor activity, and the tumor growth inhibition rate (IR) was 56.0% (p < 0.05). In summary, our study on Pm(III) complex 1 revealed promising results in in vitro and in vivo antitumor activity assays.

Complexes of lanthanides(iii) with mixed 2,2′-bipyridyl and 5,7-dibromo-8-quinolinoline chelating ligands as a new class of promising anti-cancer agents

MeOMBrQ-Ho induced HeLa cell apoptosis was mediated by inhibition of telomerase activity and dysfunction of mitochondria. Remarkably, MeOMBrQ-Ho obviously inhibited HeLa xenograft tumor growth in vivo.

Synthesis, Cytotoxic Evaluation, and Molecular Docking Studies of N-(7- hydroxy-4-methyl-2-oxoquinolin-1(2H)-yl)acetamide/benzamide Analogues

Background:

Cancer caused nearly 8.8 million deaths in 2015. Limited efficacy, selectivity, drug resistance and toxicity are major complications associated with chemotherapy, potentiating the discovery of anticancer agents.

Methods:

A new series of N-(7-hydroxy-4-methyl-2-oxoquinolin-1(2H)-yl)acetamide/benzamide analogues (5a-j) was prepared from the precursor, 7-hydroxy-4-methyl-2H-chromen-2-one (3), as anticancer agent. The structural assignment of quinolone analogues (5a-j) was based on spectroscopic data analyses. The cytotoxicity was tested on breast cancer cell lines (MCF7 and MDA-MB- 231) by sulforhodamine B (SRB) assay and three dose-related parameters GI50, TGI, and LC50 were calculated.

Results:

2-(2-chlorophenoxy)-N-(7-hydroxy-4-methyl-2-oxoquinolin-1(2H)-yl)acetamide (5a) showed the most potent cytotoxicity against the MCF7 and MDA-MB-231 cancer cell lines with GI50 of 18.7 and 48.1 &#181;M respectively. The glide scores of the compounds, 5a-d were found to be related to the cytotoxicity profile and the emodel scores for ligands, 5a-j were found to be related to significant cytotoxicity.

Conclusion:

Compound 5a exhibited the most potent cytotoxicity and this report may provide some predictions to design more potent novel quinolines as cytotoxic agents.