Design, synthesis and biological evaluation of 6-(nitroimidazole-1H-alkyloxyl)-4-anilinoquinazolines as efficient EGFR inhibitors exerting cytotoxic effects both under normoxia and hypoxia

A review on pyrimidine-based pharmacophore as a template for the development of hybrid drugs with anticancer potential

The low efficacy and toxicity of traditional chemotherapy, led by drug resistance of targeted anticancer therapies, have mandated the exploration and development of anticancer molecules. In this league, hybrid drugs, owing to their peculiar multitargeted functionality and structural diversity, could serve as vital leads in this quest for drug discovery. They are plausibly found to offer added advantages considering the improved efficacy, low toxicity, and improved patient compliance. Among numerous heterocycles explored, pyrimidine derivatives epitomize as a valuable resource for the hybrid drug development due to their validated efficacy and versatility. The present review discusses the role of pyrimidine, a diversified pharmacophore in drug development and concepts of hybrid drugs. The study covers the recent advancements in pyrimidine-based hybrid pharmacophores. It delves further into the challenges in hybrid drug development and ongoing research in hybrid drug discovery. Furthermore, the challenges faced in developing hybrid molecules, such as their design and optimization complexities, bioavailability and pharmacokinetics issues, target identification and validation, and off-target effects, are discussed.

Unraveling the future: Innovative design strategies and emerging challenges in HER2-targeted tyrosine kinase inhibitors for cancer therapy

Human epidermal growth factor receptor 2 (HER2) is a transmembrane receptor-like protein with tyrosine kinase activity that plays a vital role in processes such as cell proliferation, differentiation, and angiogenesis. The degree of malignancy of different cancers, notably breast cancer, is strongly associated with HER2 amplification, overexpression, and mutation. Currently, widely used clinical HER2 tyrosine kinase inhibitors (TKIs), such as lapatinib and neratinib, have several drawbacks, including susceptibility to drug resistance caused by HER2 mutations and adverse effects from insufficient HER2 selectivity. To address these issues, it is essential to create innovative HER2 TKIs with enhanced safety, effectiveness against mutations, and high selectivity. Typically, SPH5030 has advanced to phase I clinical trials for its strong suppression of four HER2 mutations. This review discusses the latest research progress in HER2 TKIs, with a focus on the structural optimization process and structure-activity relationship analysis. In particular, this study highlights promising design strategies to address these challenges, providing insightful information and inspiration for future development in this field.

Development of new TAK-285 derivatives as potent EGFR/HER2 inhibitors possessing antiproliferative effects against 22RV1 and PC3 prostate carcinoma cell lines

Epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) protein tyrosine kinases co-expressed in various cancers such as ovarian, breast, colon, and prostate subtypes. Herein, new TAK-285 derivatives (9a-h) were synthesised, characterised, and biologically evaluated as dual EGFR/HER2 inhibitors. Compound 9f exhibited IC₅₀ values of 2.3 nM over EGFR and 234 nM over HER2, which is 38-fold of staurosporine and 10-fold of TAK-285 over EGFR. Compound 9f also showed high selectivity profile when tested over a small kinase panel. Compounds 9a-h showed IC₅₀ values in the range of 1.0-7.3 nM and 0.8-2.8 nM against PC3 and 22RV1 prostate carcinoma cell lines, respectively. Cell cycle analysis, apoptotic induction, molecular docking, dynamics, and MM-GBSA studies confirmed the plausible mechanism(s) of compound 9f as a potent EGFR/HER2 dual inhibitor with an effective antiproliferative action against prostate carcinoma.

Design, Synthesis, Biological Evaluation, and Molecular Dynamics Studies of Novel Lapatinib Derivatives

Co-expression of the epidermal growth factor receptor (EGFR, also known as ErbB1) and human epidermal growth factor receptor 2 (HER2) has been identified as a diagnostic or prognostic sign in various tumors. Despite the fact that lapatinib (EGFR/HER2 dual inhibitor) has shown to be successful, many patients do not respond to it or develop resistance for a variety of reasons that are still unclear. As a result, new approaches and inhibitory small molecules are still needed for EGFR/HER2 inhibition. Herein, novel lapatinib derivatives possessing 4-anilinoquinazoline and imidazole scaffolds (6a-l) were developed and screened as EGFR/HER2 dual inhibitors. In vitro and in silico investigations revealed that compound 6j has a high affinity for the ATP-binding regions of EGFR and HER2. All of the designed candidates were predicted to not penetrate the BBB, raising the expectation for the absence of CNS side effects. At 10 µM, derivatives possessing 3-chloro-4-(pyridin-2-ylmethoxy)aniline moiety (6i-l) demonstrated outstanding ranges of percentage inhibition against EGFR (97.65-99.03%) and HER2 (87.16-96.73%). Compound 6j showed nanomolar IC₅₀ values over both kinases (1.8 nM over EGFR and 87.8 nM over HER2). Over EGFR, compound 6j was found to be 50-fold more potent than staurosporine and 6-fold more potent than lapatinib. A kinase selectivity panel of compound 6j showed poor to weak inhibitory activity over CDK2/cyclin A, c-MET, FGFR1, KDR/VEGFR2, and P38a/MAPK14, respectively. Structure-activity relationship (SAR) that were obtained with different substitutions were justified. Additionally, molecular docking and molecular dynamics studies revealed insights into the binding mode of the target compounds. Thus, compound 6j was identified as a highly effective and dual EGFR/HER2 inhibitor worthy of further investigation.

Design, synthesis and biological evaluation of novel tumor hypoxia-activated EGFR tyrosine kinase inhibitors

Hypoxia is widespread in solid tumors, such as NSCLC, and has become a very attractive target. On the basis of AZD9291 scaffold, novel hypoxia-targeted EGFR inhibitors without the acrylamide warhead but containing hypoxic reductive activation groups were described. Among them, compound JT21 exhibited impressive inhibitory activity (IC₅₀ = 23 nM) against EGFR^L858R/T790M and displayed about 21-fold inhibitory activity decrease against EGFR^wt. Under hypoxia, JT21 exhibited more significant proliferation inhibitory activities against H1975 cells (IC₅₀ = 7.39 ± 2.20 nM) and HCC827 cells (IC₅₀ = 5.88 ± 0.85 nM) than that of AZD9291, which was about 5 times more effective than normoxia activities. Meanwhile, the weak inhibition effects on A549 and BEAS-2B cells suggested JT21 might be a selective inhibitor for EGFR mutations with low toxicity. Furthermore, JT21 could induce apoptosis of H1975 cells under hypoxia and showed good bio-reductive property.

Concept of Hybrid Drugs and Recent Advancements in Anticancer Hybrids

Cancer is a complex disease, and its treatment is a big challenge, with variable efficacy of conventional anticancer drugs. A two-drug cocktail hybrid approach is a potential strategy in recent drug discovery that involves the combination of two drug pharmacophores into a single molecule. The hybrid molecule acts through distinct modes of action on several targets at a given time with more efficacy and less susceptibility to resistance. Thus, there is a huge scope for using hybrid compounds to tackle the present difficulties in cancer medicine. Recent work has applied this technique to uncover some interesting molecules with substantial anticancer properties. In this study, we report data on numerous promising hybrid anti-proliferative/anti-tumor agents developed over the previous 10 years (2011–2021). It includes quinazoline, indole, carbazole, pyrimidine, quinoline, quinone, imidazole, selenium, platinum, hydroxamic acid, ferrocene, curcumin, triazole, benzimidazole, isatin, pyrrolo benzodiazepine (PBD), chalcone, coumarin, nitrogen mustard, pyrazole, and pyridine-based anticancer hybrids produced via molecular hybridization techniques. Overall, this review offers a clear indication of the potential benefits of merging pharmacophoric subunits from multiple different known chemical prototypes to produce more potent and precise hybrid compounds. This provides valuable knowledge for researchers working on complex diseases such as cancer.

An appraisal of anticancer activity with structure-activity relationship of quinazoline and quinazolinone analogues through EGFR and VEGFR inhibition: A review

Cancer is one of the leading causes of death. Globally a huge number of deaths and new incidences are reported annually. Heterocyclic compounds have been proved to be very effective in the treatment of different types of cancer. Among different heterocyclic scaffolds, quinazoline and quinazolinone core were found versatile and interesting with many biological activities. In the discovery of novel anticancer agents, the Quinazoline core is very effective. The FDA has approved more than 20 drugs as an anticancer bearing quinazoline or quinazolinone core in the last two decades. One prime example is Dacomitinib, which was newly approved for non-small-cell lung carcinoma treatment in 2018. These drugs work by different pathways to prevent the spread of cancer cell progression, including inhibition of different kinases, tubulin, kinesin spindle protein, and so forth. This review presented recent developments of quinazoline/quinazolinone scaffold bearing derivatives as anticancer agents acting as epidermal growth factor receptor (EGFR) vascular endothelial growth factor receptor (VEGFR), and dual EGFR/VEGFR inhibitors.

Development of hypoxia-activated PROTAC exerting a more potent effect in tumor hypoxia than in normoxia

Hypoxia is a hallmark of many solid tumors, and it causes the overexpression of a variety of proteins including the epidermal growth factor receptor (EGFR). Many antitumor prodrugs have been designed to target hypoxia. Here we report the identification of a kind of hypoxia-activated proteolysis targeting chimera (ha-PROTAC) by introducing the hypoxia-activated leaving group (1-methyl-2-nitro-1H-imidazol-5-yl)methyl or 4-nitrobenzyl into the structure of an EGFR^Del19-based PROTAC. Among the obtained molecules, ha-PROTAC 13 exhibits a more potent degradation activity for EGFR^Del19 in hypoxia than in normoxia in HCC4006 cells. This is the first example of identifying a PROTAC to selectively act on tumors utilizing the characteristic of tumor hypoxia and provides a new approach for PROTAC development.

Bestowal of Quinazoline Scaffold in Anticancer Drug Discovery

BACKGROUND

Cancer is one of the major causes of human mortality worldwide. A number of existing antineoplastic medications and treatment regimens are already working in the field, and several new compounds are in different phases of clinical trials. An extensive series of anticancer drugs exist in the market, and studies suggest that these molecules are associated with different types of adverse side effects. The reduction of the cytotoxicity of drugs to normal cells is a major problem in anticancer therapy. Therefore, researchers around the globe are involved in the development of more efficient and safer anticancer drugs. The output of extensive research is that the quinazoline scaffold and its various derivatives can be explored further as a novel class of cancer chemotherapeutic agents that has already shown promising activities against different tumours. Quinazoline derivatives have already occupied a crucial place in modern medicinal chemistry. Various research has been performed on quinazoline and their derivatives for anticancer activity and pharmacological importance of this scaffold has been well established.

OBJECTIVE

The aim of this review is to compile and highlight the developments concerning the anticancer activity of quinazoline derivatives as well as to suggest some new aspects of the expansion of anticancer activity of novel quinazoline derivatives as anticancer agents in the near future.

METHODS

Recent literature related to quinazoline derivatives endowed with encouraging anticancer potential is reviewed. With a special focus on quinazoline moiety, this review offers a detailed account of multiple mechanisms of action of various quinazoline derivatives: inhibition of the DNA repair enzyme system, inhibition of EGFR, thymidylate enzyme inhibition and inhibitory effects for tubulin polymerization by which these derivatives have shown promising anticancer potential.

RESULTS

Exhaustive literature survey indicated that quinazoline derivatives are associated with properties of inhibiting EGFR and thymidylate enzymes. It was also found to be involved in disturbing tubulin assembly. Furthermore, quinazoline derivatives have been found to inhibit critical targets such as DNA repair enzymes. These derivatives have shown significant activity against cancer.

CONCLUSION

In cancer therapy, Quinazoline derivatives seems to be quite promising and act through various mechanisms that are well established. This review has shown that quinazoline derivatives can further be explored for the betterment of chemotherapy. A lot of potentials are still hidden, which demands to be discovered for upgrading quinazoline derivatives efficacy.

Hybridization of Imidazole with Various Heterocycles in Targeting Cancer: A Decade's Work

Cancer is the world‘s biggest global health concern. The prevalence and mortality rates of cancer remain high despite significant progress in cancer therapy. The search for more effective, as well as less toxic treatment methods for cancer, is at the focus of current studies. Approximately 24.6 million people are suffering from cancer across the world as per the world health organization (WHO). In the year 2020, approximately 10 million deaths were reported due to cancer which has emerged as the second leading cause of mortality across the globe. Anticancer medicines have played a pivotal role in the medication of different types of cancers; however, they are associated with several side effects and relevance of drug resistance which evoke an immediate need for designing of new anticancer agents with multitargeted effect. Imidazole is a heterocyclic compound privileged with considerable anticancer activities and some imidazole derivatives have already got approval to treat cancer. Many hybrid molecules are available that play an important role in the treatment of cancer like chalcone, pyrazole, purine, triazine etc., and their pharmacophore provide the anticancer drug with low drug resistance and high efficacy, with low chances of toxicity and side effects. This review provides various approaches for the drug development of new safe and efficient antitumor agents imidazole hybrids with other heterocyclic moieties. An attempt has been made to advancement of the anticancer potential of the derivatives and hybrids of imidazole having intact or condensed imidazole moiety in the last decade along with the structure‐activity relationship studies, and mechanism of action.

Have molecular hybrids delivered effective anti-cancer treatments and what should future drug discovery focus on?

INTRODUCTION

Cancer continues to be a big threat and its treatment is a huge challenge among the medical fraternity. Conventional anti-cancer agents are losing their efficiency which highlights the need to introduce new anti-cancer entities for treating this complex disease. A hybrid molecule has a tendency to act through varied modes of action on multiple targets at a given time. Thus, there is the significant scope with hybrid compounds to tackle the existing limitations of cancer chemotherapy.

AREA COVERED

This perspective describes the most significant hybrids that spring hope in the field of cancer chemotherapy. Several hybrids with anti-proliferative/anti-tumor properties currently approved or in clinical development are outlined, along with a description of their mechanism of action and identified drug targets.

EXPERT OPINION

The success of molecular hybridization in cancer chemotherapy is quite evident by the number of molecules entering into clinical trials and/or have entered the drug market over the past decade. Indeed, the recent advancements and co-ordinations in the interface between chemistry, biology, and pharmacology will help further the advancement of hybrid chemotherapeutics in the future.List of abbreviations: Deoxyribonucleic acid, DNA; national cancer institute, NCI; peripheral blood mononuclear cells, PBMC; food and drug administration, FDA; histone deacetylase, HDAC; epidermal growth factor receptor, EGFR; vascular endothelial growth factor receptor, VEGFR; suberoylanilide hydroxamic acid, SAHA; farnesyltransferase inhibitor, FTI; adenosine triphosphate, ATP; Tamoxifen, TAM; selective estrogen receptor modulator, SERM; structure activity relationship, SAR; estrogen receptor, ER; lethal dose, LD; half maximal growth inhibitory concentration, GI₅₀; half maximal inhibitory concentration, IC₅₀.

Metronidazole-conjugates: A comprehensive review of recent developments towards synthesis and medicinal perspective

Nitroimidazoles based compounds remain a hot topic of research in medicinal chemistry due to their numerous biological activities. Moreover, many clinical candidates based on this chemical core have been reported to be valuable in the treatment of human diseases. Metronidazole (MTZ) derived conjugates demonstrated a potential application in medicinal chemistry research over the last decade. In this review, we summarize the synthesis, key structure-activity-relationship (SAR) and associated biological activities such as antimicrobial, anticancer, antidiabetic, anti-inflammatory, anti-HIV and anti-parasitic (Anti-trichomonas, antileishmanial, antiamoebic and anti-giardial) of explored MTZ-conjugates. The molecular docking analysis is also presented simultaneously, which will assist in developing an understanding towards designing of new MTZ-conjugates for target-based drug discovery against multiple disease areas.

Novel quinazoline-based EGFR kinase inhibitors: A review focussing on SAR and molecular docking studies (2015-2019)

The over expression of EGFR has been recognized as the driver mechanism in the occurrence and progression of carcinomas such as lung cancer, breast cancer, pancreatic cancer, etcetera. EGFR receptor was thus established as an important target for the management of solid tumors. The occurrence of resistance caused as a result of mutations in EGFR has presented a formidable challenge in the discovery of novel inhibitors of EGFR. This has resulted in the development of three generations of EGFR TKIs. Newer mutations like C797S cause failure of Osimertinib and other EGFR TKIs belonging to the third-generation caused by the development of resistance. In this review, we have summarized the work done in the last five years to overcome the limitations of currently marketed drugs, giving structural activity relationships of quinazoline-based lead compounds synthesized and tested recently. We have also highlighted the shortcomings of the currently used approaches and have provided guidance for circumventing these limitations. Our review would help medicinal chemists streamline and guide their efforts towards developing novel quinazoline-based EGFR inhibitors.

Purine/purine isoster based scaffolds as new derivatives of benzamide class of HDAC inhibitors

This study reports the design, synthesis and evaluation of a series of histone deacetylase (HDAC) inhibitors containing purine/purine isoster as a capping group and an N-(2-aminophenyl)-benzamide unit. In vitro cytotoxicity studies reveal that benzamide 14 suppressed the growth of triple-negative breast cancer cells MDA-MB-231 (IC₅₀ = 1.48 μM), MDA-MB-468 (IC₅₀ = 0.65 μM), and liver cancer cells HepG2 (IC₅₀ = 2.44 μM), better than MS-275 (5) and Chidamide (6). Compared to the well-known HDAC inhibitor SAHA, 14 showed a higher toxicity (IC₅₀ = 0.33 μM) in three leukemic cell lines, K-562, KG-1 and THP-1. Moreover, 14 was found to be equally virulent in the HDAC-sensitive and -resistant gastric cell lines, YCC11 and YCC3/7, respectively, indicating the potential of 14 to overcome HDACi resistance. Furthermore, substantial inhibitory effects more pronounced than MS-275 (5) and Chidamide (6) were displayed by 14 towards HDAC1, 2 and 3 isoforms with IC₅₀ values of 0.108, 0.585 and 0.563 μM respectively. Compound 14 also exhibited a potent antitumor efficacy in human MDA-MB-231 breast cancer xenograft mouse model, providing a potential lead for the development of anticancer agents.

Design, synthesis, and biological study of 4-[(2-nitroimidazole-1H-alkyloxyl)aniline]-quinazolines as EGFR inhibitors exerting cytotoxicities both under normoxia and hypoxia

Purpose

In order to get novel EGFR inhibitors exerting more potency in tumor hypoxia than in normoxia.

Methods

A series of 4-[(2-nitroimidazole-1H-alkyloxyl)aniline]-quinazolines were designed and synthesized, and their in vitro cytotoxicity and EGFR inhibitory activity were evaluated. Molecule docking study was performed for the representative compound.

Results

The structure-activity relationship (SAR) studies revealed that compounds bearing both meta-chloride and para-(2-nitroimidazole-1H-alkyloxy) groups on the aniline displayed potent inhibitory activities both in enzymatic and cellular levels. The most promising compound 16i potently inhibited EGFR with an IC₅₀ value of 0.12 μM. Meanwhile, it manifested more potent cytotoxicity than the positive control lapatinib under tumor normoxia and hypoxia conditions (IC₅₀ values of 1.59 and 1.09 μM against A549 cells, 2.46 and 1.35 μM against HT-29 cells, respectively). The proposed binding model of 16i in complex with EGFR was displayed by the docking results.

Conclusion

This study provides insights for developing hypoxia-activated kinase inhibitors.

Nitro-Group-Containing Drugs

The nitro group is considered to be a versatile and unique functional group in medicinal chemistry. Despite a long history of use in therapeutics, the nitro group has toxicity issues and is often categorized as a structural alert or a toxicophore, and evidence related to drugs containing nitro groups is rather contradictory. In general, drugs containing nitro groups have been extensively associated with mutagenicity and genotoxicity. In this context, efforts toward the structure-mutagenicity or structure-genotoxicity relationships have been undertaken. The current Perspective covers various aspects of agents that contain nitro groups, their bioreductive activation mechanisms, their toxicities, and approaches to combat their toxicity issues. In addition, recent advances in the field of anticancer, antitubercular and antiparasitic agents containing nitro groups, along with a patent survey on hypoxia-activated prodrugs containing nitro groups, are also covered.

Exploiting polypharmacology for improving therapeutic outcome of kinase inhibitors (KIs): An update of recent medicinal chemistry efforts

Polypharmacology has been increasingly advocated for the therapeutic intervention in complex pathological conditions, exemplified by cancer. Although kinase inhibitors (KIs) have revolutionized the treatment for certain types of malignancies, some major medical needs remain unmet due to the relentless advance of drug resistance and insufficient efficacy of mono-target KIs. Hence, "multiple targets, multi-dimensional activities" represents an emerging paradigm for innovative anti-cancer drug discovery. Over recent years, considerable leaps have been made in pursuit of kinase-centric polypharmacological anti-cancer therapeutics, providing avenues to tackling the limitation of mono-target KIs. In the review, we summarize the clinically important mechanisms inducing KI resistance and depict a landscape of recent medicinal chemistry efforts on exploring kinase-centric polypharmacological anti-cancer agents that targeting multiple cancer-related processes. In parallel, some inevitable challenges are emphasized for the sake of more accurate and efficient drug discovery in the field.

Design and Synthesis of Vandetanib Derivatives Containing Nitroimidazole Groups as Tyrosine Kinase Inhibitors in Normoxia and Hypoxia

Sixteen novel epidermal growth factor receptor (EGFR)/vascular endothelial growth factor (VEGF)-2 inhibitors (nitroimidazole-substituted 4-anilinoquinazoline derivatives (16a–p)) were designed and prepared via the introduction of a nitroimidazole group in the piperidine side chain and modification on the aniline moiety of vandetanib. Preliminary biological tests showed that comparing with vandetanib, some target compounds exhibited excellent EGFR inhibitory activities and anti-proliferative over A549/H446 cells in hypoxia. Meanwhile, several of the above compounds demonstrated better bioactivity than vandetanib in VEGF gene expression inhibition. Owing to the excellent IC₅₀ value (1.64 μmol/L), the inhibition ratios of 16f over A549 and H446 cells were 62.01% and 59.86% at the concentration of 0.5 μM in hypoxia, respectively. All of these results indicated that 16f was a potential cancer therapeutic agent in hypoxia and was worthy of further development.

Design, Synthesis and Biological Evaluation of Benzohydrazide Derivatives Containing Dihydropyrazoles as Potential EGFR Kinase Inhibitors

A series of novel benzohydrazide derivatives containing dihydropyrazoles have been synthesized as potential epidermal growth factor receptor (EGFR) kinase inhibitors and their biological activities as potential antiproliferative agents have been evaluated. Among these compounds, compound H20 exhibited the most potent antiproliferative activity against four cancer cell line variants (A549, MCF-7, HeLa, HepG2) with IC₅₀ values of 0.46, 0.29, 0.15 and 0.21 μM respectively, which showed the most potent EGFR inhibition activities (IC₅₀ = 0.08 μM for EGFR). Molecular modeling simulation studies were performed in order to predict the biological activity and activity relationship (SAR) of these benzohydrazide derivatives. These results suggested that compound H20 may be a promising anticancer agent.