Computer-aided design, synthesis, and biological evaluation of new indole-2-carboxamide derivatives as PI3Kα/EGFR inhibitors

Pyrrole-based EGFR inhibitors for the treatment of NCSLC: Binding modes and SARs investigations

The treatment of advanced non-small cell lung cancer (NSCLC) has made substantial progress due to the rapid development of small molecule targeted therapy, with dramatically prolonged survival. As an effective drug for the treatment of NSCLC, epidermal growth factor receptor (EGFR) inhibitors are currently experiencing issues like severe adverse events and drug resistance. It is urgent to develop novel types of EGFR inhibitors to overcome the abovementioned limitations. Pyrrole always works well as a probe for the creation of novel medication candidates for hard-to-treat conditions like lung cancer. Although the design, synthesis, and biological assays of pyrrole derivatives have been reported, their inhibitory actions against the receptor tyrosine kinase (RTK) EGFR have not been in-depthly studied. This review highlights the small molecule EGFR inhibitors containing pyrrole heterocyclic pharmacophores in recent years, and the research on their mechanism, biological activity, and structure-activity relationship (SAR).

Synthesis and Biological Evaluation of Furyl-Carboxamide Derivatives as Potential Anticancer Agents

Topoisomerase II (Top-II) is an essential therapeutic target in cancer treatment owing to its overexpression in a wide variety of cancerous cells, including colorectal and breast cancer. Significant efforts have been made to discover and develop competitive inhibitors of the Top-II enzyme as potential anticancer agents. Herein, molecular modeling was employed to identify a new series of furyl-2-carboxamide derivatives as potential anticancer agents. Compounds 3, 5, and 7 were synthesized and characterized with the aid of several spectroscopic techniques, such as FT-IR, NMR, and mass spectroscopy, as well as elemental analysis. The anticancer activity properties of compounds 3, 5, and 7 were evaluated in vitro using an MTT assay in a human colorectal HCT-116 cell line with different concentration dilutions. The results indicate that the anthraquinone compound 3 is 1.3-1.6 times more potent against human colon cancer HCT-116 cells than the pyridine and benzophenone compounds 7 and 5, respectively, which reveals the importance of the anthraquinone moiety in exerting the inhibitory activity of the compound. Our findings recommend that further optimization of this series would benefit colon cancer treatment.

Design, Synthesis, and Biological Evaluation of Novel MAO-A Inhibitors Targeting Lung Cancer

Lung cancer is one of the most common causes of cancer-related deaths worldwide. Monoamine Oxidase-A (MAO-A) enzyme mediates the production of reactive oxygen species (ROS) that trigger DNA damage and oxidative injury of cells resulting in tumor initiation and progression. Available MAO-A inhibitors are used as antidepressants, however, their role as anticancer agents is still under investigation. Ligand- and structure-based drug design approaches guided the discovery and development of novel MAO-A inhibitors. A series of 1H indole-2-carboxamide derivatives was prepared and characterized using 1H-NMR, 13C-NMR, and IR. The antiproliferative effects of MAO-A inhibitors were evaluated using the cell viability assay (MTT), and MAO-A activity was evaluated using MAO-A activity assay. The presumed inhibitors significantly inhibited the growth of lung cell lines in a dose- and time dependent manner. The half maximal inhibitory concentration (IC₅₀) values of MAO-A inhibitors (S1, S2, S4, S7, and S10) were 33.37, 146.1, 208.99, 307.7, and 147.2 µM, respectively, in A549. Glide docking against MAO-A showed that the derivatives accommodate MAO-A binding cleft and engage with key binding residues. MAO-A inhibitors provide significant and consistent evidence on MAO-A activity in lung cancer and present a potential target for the development of new chemotherapeutic agents.

How the structural properties of the indole derivatives are important in kinase targeted drug design?: A case study on tyrosine kinase inhibitors

Kinases are considered as important signalling enzymes that illustrate 20% of the druggable genome. Human kinase family comprises >500 protein kinases and about 20 lipid kinases. Protein kinases are responsible for the mechanism of protein phosphorylation. These are necessary for regulation of various cellular activities including proliferation, cell cycle, apoptosis, motility, growth, differentiation, etc. Their deregulation leads to disruption of many cellular processes leading to different diseases most importantly cancer. Thus, kinases are considered as valuable targets in different types of cancer as well as other diseases. Researchers around the world are actively engaged in developing inhibitors based on distinct chemical scaffolds. Indole represents as a versatile scaffold in the naturally occurring and bioactive molecules. It is also used as a privileged scaffold for the target-based drug design against different diseases. This present article aim to review the applications of indole scaffold in the design of inhibitors against different tyrosine kinases such as epidermal growth factor receptors (EGFRs), vascular endothelial growth factor receptors (VEGFRs), platelet-derived growth factor receptors (PDGFRs), etc. Important structure activity relationships (SARs) of indole derivatives were discussed. The present work is an attempt to summarize all the crucial structural information which is essential for the development of indole based tyrosine kinase inhibitors with improved potency.

New derivatives of sulfonylhydrazone as potential antitumor agents: Design, synthesis and cheminformatics evaluation

Phosphoinositide 3-kinase α (PI3Kα) is a propitious target for designing anticancer drugs. A series of new N'-(diphenylmethylene)benzenesulfonohydrazide was synthesized and characterized using FT-IR, NMR (¹H and ¹³C), HRMS, and elemental analysis. Target compounds exhibited an antiproliferative effect against the human colon carcinoma (HCT-116) cell line. Our cheminformatics analysis indicated that the para-tailored derivatives [p-NO₂ (3) and p-CF₃ (7)] have better ionization potentials based on calculated Moran autocorrelations and ionization potentials. Subsequent in vitro cell proliferation assays validated our cheminformatics results by providing experimental evidence that both derivatives 3 and 7 exhibited improved antiproliferative activities against HCT-116. Hence, our results emphasized the importance of electron-withdrawing groups and hydrogen bond-acceptors in the rational design of small-molecule chemical ligands targeting PI3Kα. These results agreed with the induced-fit docking against PI3Kα, highlighting the role of p-substituted aromatic rings in guiding the ligand-PI3Kα complex formation, by targeting a hydrophobic pocket in the ligand-binding site and forming π-stacking interactions with a nearby tryptophan residue.

Docking Studies and Antiproliferative Activities of 6-(3-aryl-2-propenoyl)-2(3H)- benzoxazolone Derivatives as Novel Inhibitors of Phosphatidylinositol 3-Kinase (PI3Kα)

BACKGROUND

Cancer is a life-threatening group of diseases and universally, the second main cause of death. The design and development of new scaffolds targeting selective cancer cells are considered a promising goal for cancer treatment.

AIMS AND OBJECTIVE

Chalcone derivatives; 6-(3-aryl-2-propenoyl)-2(3H)-benzoxazolone, were previously prepared and evaluated against the oral cavity squamous cell carcinoma cell line, HSC-2, and were reported to have remarkably high tumor selectivity. The aim of this study was to further investigate the anticancer activities of the chalcone derivatives against human colon cancer cells with a possible elucidation of their mechanism of action.

METHODS

Computational studies were conducted to explore the potential interaction of the synthesized molecules with the phosphatidylinositol-4,5-bisphosphate 3-kinaseα (PI3Kα). Biological evaluation of the antiproliferative activities associated with compounds 1-23 was carried out against the colon cancer cell line, HCT116. Lactate Dehydrogenase (LDH) activity was measured to study necrosis, while the caspase-3 activation and DNA measurements were used to evaluate apoptosis in the treated cells.

RESULTS

Glide studies against PI3Kα kinase domain demonstrated that the 6-(3-aryl-2-propenoyl)-2(3H)- benzoxazolone scaffold forms H-bond with K802, Y836, E849, V851, N853, Q859, and D933, and it fits the fingerprint of PI3Kα active inhibitors. Biological evaluation of the reported compounds in HCT116 cell line confirmed that the series inhibited PI3Kα activity and induced apoptosis via activation of caspase-3 and reduction of DNA content.

CONCLUSION

The recently developed compounds might be employed as lead structures for the design of new antitumor drugs targeting PI3Kα.

Review on Epidermal Growth Factor Receptor (EGFR) Structure, Signaling Pathways, Interactions, and Recent Updates of EGFR Inhibitors

The epidermal growth factor receptor (EGFR) belongs to the ERBB family of tyrosine kinase receptors. EGFR signaling cascade is a key regulator in cell proliferation, differentiation, division, survival, and cancer development. In this review, the EGFR structure and its mutations, signaling pathway, ligand binding and EGFR dimerization, EGF/EGFR interaction, and the progress in the development of EGFR inhibitors have been explored.

N-Phenyl-6-Chloro-4-Hydroxy-2-Quinolone-3-CarboxAmides: Molecular Docking, Synthesis, and Biological Investigation as Anticancer Agents

Cancer is a multifactorial disease and the second leading cause of death worldwide. Diverse factors induce carcinogenesis, such as diet, smoking, radiation, and genetic defects. The phosphatidylinositol 3-kinase (PI3Kα) has emerged as an attractive target for anticancer drug design. Eighteen derivatives of N-phenyl-6-chloro-4-hydroxy-2-quinolone-3-carboxamide were synthesized and characterized using FT-IR, NMR (¹H and ¹³C), and high-resolution mass spectra (HRMS). The series exhibited distinct antiproliferative activity (IC₅₀ µM) against human epithelial colorectal adenocarcinoma (Caco-2) and colon carcinoma (HCT-116) cell lines, respectively: compounds 16 (37.4, 8.9 µM), 18 (50.9, 3.3 µM), 19 (17.0, 5.3 µM), and 21 (18.9, 4.9 µM). The induced-fit docking (IFD) studies against PI3Kαs showed that the derivatives occupy the PI3Kα binding site and engage with key binding residues.

Molecular Modeling, Synthesis and Biological Evaluation of N-Phenyl-4-Hydroxy-6-Methyl-2-Quinolone-3-CarboxAmides as Anticancer Agents

The emergence of phosphatidylinositol 3-kinase (PI3Kα) in cancer development has accentuated its significance as a potential target for anticancer drug design. Twenty one derivatives of N-phenyl-4-hydroxy-6-methyl-2-quinolone-3-carboxamide were synthesized and characterized using NMR (¹H and ¹³C) and HRMS. The derivatives displayed inhibitory activity against human epithelial colorectal adenocarcinoma (Caco-2) and human colon cancer (HCT-116) cell lines: compounds 8 (IC₅₀ Caco-2 = 98 µM, IC₅₀ HCT-116 = 337 µM) and 16 (IC₅₀ Caco-2 = 13 µM, IC₅₀ HCT-116 = 240.2 µM). Results showed that compound 16 significantly affected the gene encoding AKT, BAD, and PI3K. The induced-fit docking (IFD) studies against PI3Kα demonstrated that the scaffold accommodates the kinase domains and forms H-bonds with significant binding residues.

Synthetic strategies, SAR studies, and computer modeling of indole 2 and 3-carboxamides as the strong enzyme inhibitors: a review

Abstract

Indole derivatives have been the focus of many researchers in the study of pharmaceutical compounds for many years. Researchers have investigated the effect of carboxamide moiety at positions 2 and 3, giving unique inhibitory properties to these compounds. The presence of carboxamide moiety in indole derivatives causes hydrogen bonds with a variety of enzymes and proteins, which in many cases, inhibits their activity. In this review, synthetic strategies of indole 2 and 3-carboxamide derivatives, the type, and mode of interaction of these derivatives against HLGP, HIV-1, renin enzyme, and structure–activity studies of these compounds were investigated. It is hoped that indole scaffolds will be tested in the future for maximum activity in pharmacological compounds.

Graphic abstract

Recent Development in Indole Derivatives as Anticancer Agents for Breast Cancer

BACKGROUND

Breast Cancer (BC) is the second most common cause of cancer related deaths in women. Due to severe side effects and multidrug resistance, current therapies like hormonal therapy, surgery, radiotherapy and chemotherapy become ineffective. Also, the existing drugs for BC treatment are associated with several drawbacks such as poor oral bioavailability, non-selectivity and poor pharmacodynamics properties. Therefore, there is an urgent need for the development of more effective and safer anti BC agents.

OBJECTIVE

This article explored in detail the possibilities of indole-based heterocyclic compounds as anticancer agents with breast cancer as their major target.

METHODS

Recent literature related to indole derivatives endowed with encouraging anti BC potential is reviewed. With special focus on BC, this review offers a detailed account of multiple mechanisms of action of various indole derivatives: aromatase inhibitor, tubulin inhibitor, microtubule inhibitor, targeting estrogen receptor, DNA-binding mechanism, induction of apoptosis, inhibition of PI3K/AkT/NFkB/mTOR, and HDAC inhibitors, by which these derivatives have shown promising anticancer potential.

RESULTS

Exhaustive literature survey indicated that indole derivatives are associated with properties of inducing apoptosis and disturbing tubulin assembly. Indoles are also associated with the inhibition of NFkB/mTOR/PI3K/AkT and regulation of estrogen-mediated activity. Furthermore, indole derivatives have been found to modulate critical targets such as topoisomerase and HDAC. These derivatives have shown significant activity against breast cancer cells.

CONCLUSION

In BC, indole derivatives seem to be quite competent and act through various mechanisms that are well established in case of BC. This review has shown that indole derivatives can further be explored for the betterment of BC chemotherapy. A lot of potential is still hidden which demands to be discovered for upgrading BC chemotherapy.

Ligand-Based Drug Design: Synthesis and Biological Evaluation of Substituted Benzoin Derivatives as Potential Antitumor Agents

Background:

Phosphoinositide 3-kinase α (PI3Kα) has emerged as a promising target for anticancer drug design.

Objectives:

Target compounds were designed to investigate the effect of the p-OCH3 motifs on ligand/PI3Kα complex interaction and antiproliferative activity.

Methods:

Synthesis of the proposed compounds, biological examination tests against human colon adenocarcinoma (HCT-116), breast adenocarcinoma (MCF-7), and breast carcinoma (T47D) cell lines, along with Glide docking studies.

Results:

A series of 1,2-bis(4-methoxyphenyl)-2-oxoethyl benzoates was synthesized and characterized by means of FT-IR, 1H and 13C NMR, and by elemental analysis. Biological investigation demonstrated that the newly synthesized compounds exhibit antiproliferative activity in human colon adenocarcinoma (HCT-116), breast adenocarcinoma (MCF-7), and breast carcinoma (T47D) cell lines possibly via inhibition of PI3Kα and estrogen receptor alpha (ERα). Additionally, results revealed that these compounds exert selective inhibitory activity, induce apoptosis, and suppress VEGF production. Compound 3c exhibited promising antiproliferative activity in HCT-116 interrogating that hydrogen bond-acceptor mediates ligand/PI3Kα complex formation on m- position. Compounds 3e and 3i displayed high inhibitory activity in MCF-7 and T47D implying a wide cleft discloses the o-attachment. Furthermore, compound 3g exerted selective inhibitory activity against T47D. Glide docking studies against PI3Kα and ERα demonstrated that the series accommodate binding to PI3Kα and/or ERα.

Conclusion:

The series exhibited a potential antitumor activity in human carcinoma cell lines encoding PI3Kα and/or ERα.

Synthesis, Characterization, and Biological Activity of a Novel Series of Benzo[4,5]imidazo[2,1-b]thiazole Derivatives as Potential Epidermal Growth Factor Receptor Inhibitors

Based on the analysis of epidermal growth factor receptor (EGFR) complexes with gefitinib with molecular docking, the scaffold-hopping strategy, combination of the active substructures, and structural optimization of EGFR inhibitors, a novel series of benzo[4,5]imidazo[2,1-b]thiazole derivatives was designed, synthesized, and evaluated for antitumor activity in human cancer cell lines and cellular toxicity against human normal cell lines using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay and EGFR inhibitory activities in vitro. Some target compounds such as 2-(benzo[4,5]imidazo[2,1-b]thiazol-3-yl)-N-(2-hydroxyphenyl)acetamide (D04) and 2-(benzo[4,5]imidazo[2,1-b]thiazol-3-yl)-N-(naphthalen-1-yl)acetamide (D08) have shown significant antitumor activity against the EGFR high-expressed human cell line HeLa. All the target compounds showed hardly any antitumor activity against the EGFR low-expressed human cell line HepG2, and nearly no cellular toxicity against the human normal cell lines HL7702 and human umbilical vein endothelial cell lines (HUVEC). The inhibitory activities against EGFR kinase in vitro of the three target compounds were greatly consistent with the anti-proliferative activities. The preliminary structure⁻activity relationships of the target compounds were summarized. Conclusively, the novel benzo[4,5]imidazo[2,1-b]thiazole derivatives as novel potential EGFR inhibitors may be used as the potential lead compounds for the development of antitumor agents.

5-Bromo-1-(4-chlorobenzyl)-1H-indole-2-carboxamides as new potent antibacterial agents

Ten 5-bromoindole-2-carboxamides were synthesized, characterized and evaluated for antibacterial activity against pathogenic Gram-negative bacteria Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa and Salmonella Typhi using gentamicin and ciprofloxacin as internal standards. Compounds 7a–c, 7g and 7h exhibit high antibacterial activity with a minimum inhibitory concentration (MIC) of 0.35–1.25 μg/mL. Compounds 7a–c exhibit antibacterial activities that are higher than those of the standards against E. coli and P. aeruginosa.

Synthesis, characterization, and anticancer evaluation of some new N1-(anthraquinon-2-yl) amidrazone derivatives

A new series of novel N1-anthraquinon-2-yl amidrazones incorporating N-piperazines and related congeners were synthesized via reaction of the hydrazonoyl chloride derived from 2-qaminoanthraquinone with the appropriate piperazine (secondary amine). Structures of the new compounds were confirmed by a panel of spectroscopic methods including IR, NMR, and MS and by elemental analysis. The antitumor activity of the newly prepared compounds was evaluated in vitro against MCF-7 breast cancer, K562 chronic myelogenous leukemia, and dermal fibroblasts cell lines by means of a cell viability assay using the tetrazolium dye 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. Results revealed that compounds 13a and 13d exhibit the highest inhibitory activity against K562 and MCF-7 cell lines. These two compounds could be considered as promising as potential anticancer drugs.

Novel amphiphilic pyridinium ionic liquids-supported Schiff bases: ultrasound assisted synthesis, molecular docking and anticancer evaluation

Background

Pyridinium Schiff bases and ionic liquids have attracted increasing interest in medicinal chemistry.

Results

A library of 32 cationic fluorinated pyridinium hydrazone-based amphiphiles tethering fluorinated counteranions was synthesized by alkylation of 4-fluoropyridine hydrazone with various long alkyl iodide exploiting lead quaternization and metathesis strategies. All compounds were assessed for their anticancer inhibition activity towards different cancer cell lines and the results revealed that increasing the length of the hydrophobic chain of the synthesized analogues appears to significantly enhance their anticancer activities. Substantial increase in caspase-3 activity was demonstrated upon treatment with the most potent compounds, namely 8, 28, 29 and 32 suggesting an apoptotic cellular death pathway.

Conclusions

Quantum-polarized ligand docking studies against phosphoinositide 3-kinase α displayed that compounds 2–6 bind to the kinase site and form H-bond with S774, K802, H917 and D933.

Electronic supplementary material

The online version of this article (10.1186/s13065-018-0489-z) contains supplementary material, which is available to authorized users.

Facile synthesis, characterization, and cytotoxicity study of new 3-(indol-2-yl)bicyclotetrazatridecahexaens

A new series of thiosemicarbazone-based indole derivatives 12–15 has been prepared by condensation reaction of indole-2-carboxamide derivatives 8–11 with thiosemicarbazide. The former compounds underwent intracyclization in the presence of chloroacetic acid and sodium acetate to afford a set of new 3-(indol-2-yl)bicyclotetrazatridecahexaens 16–19. These newly synthesized compounds have been characterized by means of FTIR, 1H NMR, 13C NMR, and HRMS and by elemental analyses. Cytotoxic activities of the prepared compounds along with LY294002 were evaluated in vitro against normal human skin fibroblast, human colon carcinoma (HCT116), and leukemia (K562) cell lines; results revealed that the series inhibits only HCT116 cell line. In addition, results showed that compound 18 exerts moderate potency in HCT116 with an IC50 value of 54 μmol/L and significantly induces apoptosis.