Design and discovery of 4-anilinoquinazoline-urea derivatives as dual TK inhibitors of EGFR and VEGFR-2

Exploration of cytotoxicity of iodoquinazoline derivatives as inhibitors of both VEGFR-2 and EGFRT790M: Molecular docking, ADMET, design, and syntheses

Novel inhibitors of epidermal growth factor receptor (EGFR)T790M/vascular endothelial growth factor receptor-2 (VEGFR-2) were synthesized based on the iodoquinazoline scaffold linked to different heteroaromatic, aromatic, and/or aliphatic moieties. The novel derivatives were in vitro examined for anticancer activities against A549, HCT116, michigan cancer foundation-7 (MCF-7), and HepG2 cells. Molecular modeling was applied to discover their orientation of binding with both VEGFR-2 and EGFR active sites. Compounds 8d, 8c, 6d, and 6c indicated the highest cytotoxicity with IC50 = 6.00, 6.90, 6.12 and 6.24 µM, 7.05, 7.35, 6.80, and 6.80 µM, 5.75, 7.50, 6.90, and 6.95 µM, and 6.55, 7.88, 7.44, and 7.10 µM against the A549, HepG2, HCT116, and MCF-7 cell lines, correspondingly. The cytotoxicity against normal VERO (normal african green monkey kidney cells) of the extremely active eight compounds 6a-d and 8a-d was evaluated. Our compounds exhibited low toxicity concerning normal VERO cells with IC50 = 45.66-51.83 μM. Furthermore, inhibition assays for both the EGFRT790M and VEGFR-2 enzymes were done for all compounds. Remarkable inhibition of EGFRT790M activity was achieved with compounds 6d, 8d, 6c, and 8c at IC50 = 0.35, 0.42, 0.48, and 0.50 µM correspondingly. Moreover, remarkable inhibition of VEGFR-2 activity was achieved with compounds 8d, 8c, 6d, and 6c at IC50 = 0.92, 0.95, 1.00, and 1.20 µM correspondingly. As planned, derivatives 6d, 8d, 6c, and 8c presented exceptional inhibition of both EGFRT790M/VEGFR-2 activities. Finally, in silico absorption, distribution, metabolism, excretion and toxicity (ADMET) studies were made for the highly active four compounds 6c, 6d, 8c, and 8d in comparison with erlotinib and sorafenib as reference standards.

Synthesis, biological evaluation, and molecular docking studies of novel N-substituted piperazine-tethered thiophene-3-carboxamide selenides as potent antiproliferative agents with EGFR kinase inhibitory activity

In the context of structural investigation and optimization of various potential EGFR inhibitors, a novel series of asymmetrical piperazine-tethered trisubstituted thiophene-3-carboxamide selenide derivatives were synthesized and evaluated for their antiproliferative potential against selected human cancer cell lines. These derivatives, built based on a previously identified hit molecule, were synthesized via multiple-step reactions, including optimization of the C-Se cross-coupling reaction. Two compounds, 17i and 18i, displayed significant cytotoxicity (IC50 value: 4.82 ± 0.80 µM and 1.43 ± 0.08 µM) against HCT116 and A549 cancer cell lines, respectively. Quantitative analysis of apoptotic stages using Annexin V-FITC/PI double staining validated their apoptotic potential. Further, compound 18i demonstrated a remarkable inhibition of EGFR kinase, with an IC50 concentration of 42.3 nM. The lead compound 18i, with remarkable in vitro cytotoxicity, apoptosis induction capability, and EGFR inhibition, emerges as a promising candidate for anticancer therapy.

Discovery of novel pyrazole based Urea/Thiourea derivatives as multiple targeting VEGFR-2, EGFRWT, EGFRT790M tyrosine kinases and COX-2 Inhibitors, with anti-cancer and anti-inflammatory activities

A novel series of pyrazole derivatives with urea/thiourea scaffolds 16a-l as hybrid sorafenib/erlotinib/celecoxib analogs was designed, synthesized and tested for its VEGFR-2, EGFRWT, EGFRT790M tyrosine kinases and COX-2, pro-inflammatory cytokines TNF-α and IL-6 inhibitory activities. All the tested compounds showed excellent COX-2 selectivity index in range of 18.04-47.87 compared to celecoxib (S.I. = 26.17) and TNF-α and IL-6 inhibitory activities (IC50 = 5.0-7.50, 6.23-8.93 respectively, compared to celecoxib IC50 = 8.40 and 8.50, respectively). Screening was carried out against 60 human cancer cell lines by National Cancer Institute (NCI), compounds 16a, 16c, 16d and 16 g were the most potent inhibitors with GI% ranges of 100 %, 99.63-87.02 %, 98.98-43.10 % and 98.68-23.62 % respectively, and with GI50 values of 1.76-15.50 µM, 1.60-5.38 µM, 1.68-7.39 µM and 1.81-11.0 µM respectively, in addition, of showing good safety profile against normal cell line (F180). Moreover, compounds 16a, 16c, 16d and 16 g had cell cycle arrest at G2/M phase with induced necrotic percentage compared to sorafenib of 2.06 %, 2.47 %, 1.57 %, 0.88 % and 1.83 % respectively. Amusingly, compounds 16a, 16c, 16d and 16 g inhibited VEGFR-2 with IC50 of 25 nM, 52 nM, 324 nM and 110 nM respectively, compared to sorafenib (IC50 = 85 nM), and had excellent EGFRWT and EGFRT790M kinase inhibitory activities (IC50 = 94 nM, 128 nM, 160 nM, 297 nM), (10 nM, 25 nM, 36 nM and 48 nM) respectively, compared to both erlotinib and osimertinib (IC50 = 114 nM, 56 nM) and (70 nM, 37 nM) respectively and showed (EGFRwt/EGFRT790M S.I.) of (range: 4.44-9.40) compared to erlotinib (2.03) and osmertinib (1.89).

Structural and molecular insights from dual inhibitors of EGFR and VEGFR2 as a strategy to improve the efficacy of cancer therapy

Epidermal growth factor receptor (EGFR) and vascular endothelial growth factor 2 (VEGFR2) are known as valid targets for cancer therapy. Overexpression of EGFR induces uncontrolled cell proliferation and VEGF expression triggering angiogenesis via VEGFR2 signaling. On the other hand, VEGF expression independent of EGFR signaling is already known as one of the mechanisms of resistance to anti-EGFR therapy. Therefore, drugs that act as dual inhibitors of EGFR and VEGFR2 can be a solution to the problem of drug resistance and increase the effectiveness of therapy. In this review, we summarize the relationship between EGFR and VEGFR2 signal transduction in promoting cancer growth and how their kinase domain structures can affect the selectivity of an inhibitor as the basis for designing dual inhibitors. In addition, several recent studies on the development of dual EGFR and VEGFR2 inhibitors involving docking simulations were highlighted in this paper to provide some references such as pharmacophore features of inhibitors and key residues for further research, especially in computer-aided drug design.

Iodoquinazoline-derived VEGFR-2 and EGFRT790M dual inhibitors: Design, synthesis, molecular docking and anticancer evaluations

Herein, we report the synthesis of a series of new fourteen iodoquinazoline derivatives 7a-c to 13a-e and their evaluation as potential anticancer agents via dual targeting of EGFRT790M and VEGFR-2. The new derivatives were designed according to the target receptors structural requirements. The compounds were evaluated for their cytotoxicity against HepG2, MCF-7, HCT116 and A549 cancer cell lines using MTT assay. Compound 13e showed the highest anticancer activities with IC50 = 5.70, 7.15, 5.76 and 6.50 µM against HepG2, MCF-7, HCT116 and A549 cell lines correspondingly. Compounds 7c, 9b and 13a-d exhibited very good anticancer effects against the tested cancer cell lines. The highly effective six derivatives 7c, 10, 13b, 13c, 13d and 13e were examined against VERO normal cell lines to estimate their cytotoxic capabilities. Our conclusion revealed that compounds 7c, 10, 13b, 13c, 13d and 13e possessed low toxicity against VERO normal cells with IC50 prolonging from 41.66 to 53.99 μM. Also compounds 7a-c to 13a-e were further evaluated for their inhibitory activity against EGFRT790M and VEGFR-2. Also, their ability to bind with both EGFR and VEGFR-2 receptors was examined by molecular modeling. Compounds 13e, 13d, 7c and 13c excellently inhibited VEGFR-2 activity with IC50 = 0.90, 1.00, 1.25 and 1.50 µM respectively. Moreover, Compounds 13e, 7c, 10 and 13d excellently inhibited EGFRT790M activity with IC50 = 0.30, 0.35, 0.45 and 0.47 µM respectively. Finally, our derivatives 7b, 13d and 13e showed good in silico calculated ADMET profile.

Coevolution-based computational approach to detect resistance mechanism of epidermal growth factor receptor

Tyrosine kinase epidermal growth factor receptor (EGFR) correlates the neoplastic cell metastasis, angiogenesis, neoplastic incursion, and apoptosis. Due to the involvement of EGFR in these biological processes, it becomes a most potent target for treating non-small cell lung cancer (NSCLC). The tyrosine kinase inhibitors (TKI) have endorsed high efficacy and anticipation to patients but unfortunately, within a year of treatment, drug targets develop resistance due to mutations. The present study detected the compensatory mutations in EGFR to know the evolutionary mechanism of drug resistance. The results of this study demonstrate that compensatory mutations enlarge the drug-binding pocket which may lead to the altered orientation of the ligand (gefitinib and erlotinib) causing drug resistance. This indicates that coevolutionary forces play a significant role in fine-tuning the structure of EGFR protein against the drugs. The analysis provides insight into the evolution-induced structural aspects of drug resistance changes in EGFR which in turn be useful in designing drugs with better efficacy.

Epidermal growth factor receptor dual-target inhibitors as a novel therapy for cancer: A review

Overexpression of the epidermal growth factor receptor (EGFR) has been linked to several human cancers, including esophageal cancer, pancreatic cancer, anal cancer, breast cancer, and lung cancer, particularly non-small cell lung cancer (NSCLC). Therefore, EGFR has emerged as a critical target for treating solid tumors. Many 1st-, 2nd-, 3rd-, and 4th-generation EGFR single-target inhibitors with clinical efficacy have been designed and synthesized in recent years. Drug resistance caused by EGFR mutations has posed a significant challenge to the large-scale clinical application of EGFR single-target inhibitors and the discovery of novel EGFR inhibitors. Therapeutic methods for overcoming multipoint EGFR mutations are still needed in medicine. EGFR dual-target inhibitors are more promising than single-target inhibitors as they have a lower risk of drug resistance, higher efficacy, lower dosage, and fewer adverse events. EGFR dual-target inhibitors have been developed sequentially to date, providing new options for remission in patients with previously untreatable malignancies and laying the groundwork for a future generation of compounds. This paper introduces the EGFR family proteins and their synergistic effects with other anticancer targets, and provides a comprehensive review of the development of EGFR dual-target inhibitors in cancer, as well as the opportunities and challenges associated with those fields.

Quinazoline-based VEGFR-2 inhibitors as potential anti-angiogenic agents: A contemporary perspective of SAR and molecular docking studies

Angiogenesis, the formation of new blood vessels from the existing vasculature, is pivotal in the migration, growth, and differentiation of endothelial cells in normal physiological conditions. In various types of tumour microenvironments, dysregulated angiogenesis plays a crucial role in supplying oxygen and nutrients to cancerous cells, leading to tumour size growth. VEGFR-2 tyrosine kinase has been extensively studied as a critical regulator of angiogenesis; thus, inhibition of VEGFR-2 has been widely used for cancer treatments in recent years. Quinazoline nucleus is a privileged and versatile scaffold with a broad range of pharmacological activity, especially in the field of tyrosine kinase inhibitors with more than twenty small molecule inhibitors approved by the US Food and Drug Administration in the last two decades. As of now, the U.S. FDA has approved eleven small chemical inhibitors of VEGFR-2 for various types of malignancies, with a prime example being vandetanib, a quinazoline derivative, which is a multi targeted kinase inhibitor used for the treatment of late-stage medullary thyroid cancer. Despite of prosperous discovery and development of VEGFR-2 down regulator drugs, there still exists limitations in clinical efficacy, adverse effects, a high rate of clinical discontinuation and drug resistance. Therefore, there is an urgent need for the design and synthesis of more selective and effective inhibitors to tackle these challenges. Through the gathering of this review, we have strived to broaden the extent of our view over the entire scope of quinazoline-based VEGFR-2 inhibitors. Herein, we give an overview of the importance and advancement status of reported structures, highlighting the SAR, biological evaluations and their binding modes.

New quinazoline sulfonamide derivatives as potential anticancer agents: Identifying a promising hit with dual EGFR/VEGFR-2 inhibitory and radiosensitizing activity

Herein, we report the synthesis of a series of new quinazoline sulfonamide conjugates 2-16 and their evaluation as potential anticancer agents via dual targeting of EGFRT790M and VEGFR-2. The newly synthesized compounds were designed based on the structure requirements of the target receptors and were confirmed using spectral data. The compounds were evaluated for their cytotoxicity against four cancer cell lines (HepG2, MCF-7, HCT116 and A549) using MTT assay. The most active compounds were further evaluated for their inhibitory activity against EGFRT790M and VEGFR-2. Compound 15 showed the most significant cytotoxic activity with IC50 = 0.0977 µM against MCF-7 and the most potent inhibitory activity against both EGFR and VEGFR with IC50 = 0.0728 and 0.0523 µM, respectively. Compound 15 was able to induce apoptosis in MCF-7 cells and cell cycle arrest at the G2/M phase. The relative safety profile of 15 was assessed using HEK-293 normal cell line and an ADMET profile was carried out. Radiosensitizing evaluation of 15 proved its significant ability to sensitize the cancer cell to the effect of radiation after being subjected to a single dose of 8 Gy gamma irradiation. Molecular docking studies revealed that 15 could bind to the ATP-binding site of EGF and VEGF receptors, inhibiting their activity.

Structure-Activity Relationship Studies Based on Quinazoline Derivatives as EGFR Kinase Inhibitors (2017-Present)

The epidermal growth factor receptor (EGFR) plays a critical role in the tumorigenesis of various forms of cancer. Targeting the mutant forms of EGFR has been identified as an attractive therapeutic approach and led to the approval of three generations of inhibitors. The quinazoline core has emerged as a favorable scaffold for the development of novel EGFR inhibitors due to increased affinity for the active site of EGFR kinase. Currently, there are five first-generation (gefitinib, erlotinib, lapatinib, vandetanib, and icotinib) and two second-generation (afatinib and dacomitinib) quinazoline-based EGFR inhibitors approved for the treatment of various types of cancers. The aim of this review is to outline the structural modulations favorable for the inhibitory activity toward both common mutant (del19 and L858R) and resistance-conferring mutant (T790M and C797S) EGFR forms, and provide an overview of the newly synthesized quinazoline derivatives as potentially competitive, covalent or allosteric inhibitors of EGFR.

Recent development of multi-target VEGFR-2 inhibitors for the cancer therapy

Vascular epidermal growth factor receptor-2 (VEGFR-2), as an important tyrosine transmembrane protein, plays an important role in regulating endothelial cell proliferation and migration, regulating angiogenesis and other biological functions. VEGFR-2 is aberrantly expressed in many malignant tumors, and it is also related to the occurrence, development, and growth of tumors and drug resistance. Currently, there are nine VEGFR-2 targeted inhibitors approved by US.FDA for clinical use as anticancer drugs. Due to the limited clinical efficacy and potential toxicity of VEGFR inhibitors, it is necessary to develop new strategies to improve the clinical efficacy of VEGFR inhibitors. The development of multitarget therapy, especially dual-target therapy, has become a hot research field of cancer therapy, which may provide an effective strategy with higher therapeutic efficacy, pharmacokinetic advantages and low toxicity. Many groups have reported that the therapeutic effects could be improved by simultaneously inhibiting VEGFR-2 and other targets, such as EGFR, c-Met, BRAF, HDAC, etc. Therefore, VEGFR-2 inhibitors with multi-targeting capabilities have been considered to be promising and effective anticancer agents for cancer therapy. In this work, we reviewed the structure and biological functions of VEGFR-2, and summarized the drug discovery strategies, and inhibitory activities of VEGFR-2 inhibitors with multi-targeting capabilities reported in recent years. This work might provide the reference for the development of VEGFR-2 inhibitors with multi-targeting capabilities as novel anticancer agents.

Medicinal Chemistry of Quinazolines as Anticancer Agents Targeting Tyrosine Kinases

Cancer is a large group of diseases that can affect any organ or body tissue due to the abnormal cellular growth with the unknown reasons. Many of the existing chemotherapeutic agents are highly toxic with a low level of selectivity. Additionally, they lead to development of therapeutic resistance. Hence, the development of targeted chemotherapeutic agents with low side effects and high selectivity is required for cancer treatment. Quinazoline is a vital scaffold well-known to be linked with several biological activities. The anticancer activity is one of the prominent biological activities of this scaffold. Several established anticancer quinazolines work by different mechanisms on the various molecular targets. The aim of this review is to present different features of medicinal chemistry as drug design, structure activity relationship, and mode of action of some targeted anticancer quinazoline derivatives. It gives comprehensive attention on the chemotherapeutic activity of quinazolines in the viewpoint of drug discovery and its development. This review provides panoramic view to the medicinal chemists for supporting their efforts to design and synthesize novel quinazolines as targeted chemotherapeutic agents.

Search for potentially biased epidermal growth factor receptor (EGFR) inhibitors through pharmacophore modelling, molecular docking, and molecular dynamics (MD) simulation approaches

Epidermal growth factor receptor (EGFR), being one of the most crucial receptor in cancer therapy, has been selected as a potential target for the present study. Ligand-based pharmacophore model (n = 30, R²=0.93 with root mean square deviation = 1.14, ΔCost = 144.27 and configuration cost = 21) was developed and validated with Fischer's randomisation (at 95% confidence), test set (n = 225, R² pred = 0.81), external data set (n = 13, R² pred = 0.95) and decoy set (n = 70), further the model has been used to search for novel EGFR inhibitors. The validated model was used for virtual screening of zinc database. A pool of 115,948 candidate molecules was screened through the model. Subsequently, molecules having predicted IC₅₀<0.2 µM were selected for screening through drug-like properties filter. Based on pharmacokinetic profile (ADMET study), Lipinski's rule of five and Veber's rule, 62 molecules were shortlisted for molecular docking. Using consensus docking, five hit molecules were selected, which were further considered for molecular dynamics simulation. Additionally MM-GBSA analysis was carried which showed that affinity of hits towards the receptor of three compound mainly ZINC305, ZINC131796 and ZINC131785 were similar to the standard vanedtinib. The simulation, performed for 100 ns, revealed that two hit molecules, namely ZINC305 and ZINC131785, showing potential interactions at the ligand-binding domain of EGFR protein with good ligand-protein stability. Communicated by Ramaswamy H. Sarma.

Exploration of thiazolidine-2,4-diones as tyrosine kinase inhibitors: Design, synthesis, ADMET, docking, and antiproliferative evaluations

As dual EGFR and VEGFR-2 inhibitors, 22 innovative thiazolidine-2,4-diones were modeled, constructed, and measured for their anticancer performance versus four human neoplasms HCT-116, MCF-7, A549, and HepG2. Molecular docking and MD simulation were performed to inspect the binding technique of the proffered congeners with the EGFR and VEGFR-2 receptors. Evidence realized thanks to the docking inquests was vastly consistent together with that detected through the biological screening. Structures 14a and 14g emerged as the most active compounds toward HCT116 (IC₅₀  = 6.01 and 7.44 µM), MCF-7 (IC₅₀  = 5.77 and 7.23 µM), A549 (IC₅₀  = 5.35 and 5.47 µM) and HepG2 (IC₅₀  = 3.55 and 3.85 µM) tumefaction cells. Compounds 14a and 14g exhibited higher events than sorafenib (IC₅₀  = 5.05, 5.58, 4.04, and 4.00 µM) against HepG2 instead subordinate incidents concerning A549, MCF-7, and HCT116, parallelly. Nevertheless, these compounds signified weightier performance than erlotinib (IC₅₀  = 13.91, 8.20, 5.49, 7.73, and µM), with respect to the four cell lines. Compounds having the best activity against the four cell lines, 12a-f, 13a-d, and 14a-g were chosen to appraise their in vitro VEGFR-2 and EGFR^T790M inhibiting activities. The best results were for compounds 14a and 14g compared to sorafenib and erlotinib, respectively, with IC₅₀ values of 0.74 and 0.78 µM and 0.12 and 0.14 µM, respectively. Moreover, 13d, 14a, and 14g showed an adequate in silico calculated ADMET profile. The current investigation presents novel candidates for future optimization to construct mightier and eclectic binary VEGFR-2/EGFR^T790M restrainers with higher antitumor effects.

Cobalt(III)-catalyzed weakly coordinating arylurea-directed regioselective mono-olefination

Here, we developed an air-stable, earth-abundant cobalt(III)-catalyzed regioselective mono-olefination of arenes directed by urea under mild conditions through a cross-dehydrogenative coupling (CDC) process. Under the optimized conditions, a high regioselectivity of mono-olefination was achieved with various electron-rich and electron-deficient arenes, which afforded E-alkenylated products (with yields of up to 90%). In contrast to the conditions used for noble-metal-catalyzed olefination directed by weakly coordinating groups, our reaction was operated under mild conditions, including mild temperature (40 °C) and non-metallic oxidant.

Design, synthesis and molecular docking of new fused 1H-pyrroles, pyrrolo[3,2-d]pyrimidines and pyrrolo[3,2-e][1, 4]diazepine derivatives as potent EGFR/CDK2 inhibitors

A new series of 1H-pyrrole (6a-c, 8a-c), pyrrolo[3,2-d]pyrimidines (9a-c) and pyrrolo[3,2-e][1, 4]diazepines (11a-c) were designed and synthesised. These compounds were designed to have the essential pharmacophoric features of EGFR Inhibitors, they have shown anticancer activities against HCT116, MCF-7 and Hep3B cancer cells with IC₅₀ values ranging from 0.009 to 2.195 µM. IC₅₀ value of doxorubicin is 0.008 µM, compounds 9a and 9c showed IC₅₀ values of 0.011 and 0.009 µM respectively against HCT-116 cells. Compound 8b exerted broad-spectrum activity against all tested cell lines with an IC₅₀ value less than 0.05 µM. Compound 8b was evaluated against a panel of kinases. This compound potently inhibited CDK2/Cyclin A1, DYRK3 and GSK3 alpha kinases with 10-23% compared to imatinib (1-10%). It has also arrested the cell cycle of MCF-7 cells at the S phase. Its antiproliferative activity was further augmented by molecular docking into the active sites of EGFR and CDK2 cyclin A1.

Discovery of new 1H-pyrazolo[3,4-d]pyrimidine derivatives as anticancer agents targeting EGFRWT and EGFRT790M

New 1H-pyrazolo[3,4-d]pyrimidine derivatives were designed and synthesised to act as epidermal growth factor receptor inhibitors (EGFRIs). The synthesised derivatives were assessed for their in vitro anti-proliferative activities against A549 and HCT-116 cancer cells. Compounds 8, 10, 12a, and 12b showed potent anti-proliferative activities. Compound 12b was the most promising member with IC₅₀ values of 8.21 and 19.56 µM against A549 and HCT-116, respectively. Compounds 8, 10, 12a, and 12b were evaluated for their kinase inhibitory activities against wild EGFR (EGFR^WT). Compound 12b was the most potent member showing an IC₅₀ value of 0.016 µM. In addition, compound 12b showed noticeable activity against mutant EGFR (EGFR^T790M) (IC₅₀ = 0.236 µM). Flow cytometric analyses revealed that compound 12b is a good apoptotic inducer and can arrest the cell cycle at S and G2/M phases. Furthermore, it produced an 8.8-fold increase in BAX/Bcl-2 ratio. Molecular docking studies were carried out against EGFR^WT and EGFR^T790M.

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.

Design, synthesis and biological evaluation of erlotinib-based IDO1 inhibitors

Erlotinib is a highly specific and reversible epidermal growth factor receptor tyrosine kinase inhibitor for the targeted therapy of non-small-cell lung cancer (NSCLC) However, the efficacy of erlotinib is limited because the development of drug resistance during chemotherapy. Indoleamine 2,3-dioxygenase-1 (IDO1) is a rate-limiting tryptophan catabolic enzyme that is activated in many human cancers. In this study, we designed a series of erlotinib-based 1,2,3-triazole compounds by combining erlotinib with phenyl or benzyl azide. Attentive FP prediction model was used to predict the bioactivity of those compounds. We discovered that most of the erlotinib-based 1,2,3-triazole compounds are capable of suppressing IDO1 activities in vitro experiments. Among them, compound 14b (IC50 = 0.59 ± 0.05 μM) had the strongest inhibitory effect on IDO1. In addition, compound 14b significantly inhibited tumor growth comparable to the antitumor activity of erlotinib and the IDO1 inhibitor epacadostat in murine tumor models.

Emerging strategies to overcome resistance to third-generation EGFR inhibitors

Epidermal growth factor receptor (EGFR), the receptor for members of the epidermal growth factor family, regulates cell proliferation and signal transduction; moreover, EGFR is related to the inhibition of tumor cell proliferation, angiogenesis, invasion, metastasis, and apoptosis. Therefore, EGFR has become an important target for the treatment of cancer, including non-small cell lung cancer, head and neck cancer, breast cancer, glioma, cervical cancer, and bladder cancer. First- to third-generation EGFR inhibitors have shown considerable efficacy and have significantly improved disease prognosis. However, most patients develop drug resistance after treatment. The challenge of overcoming intrinsic and acquired resistance in primary and recurrent cancer mediated by EGFR mutations is thus driving the search for alternative strategies in the design of new therapeutic agents. In view of resistance to third-generation inhibitors, understanding the intricate mechanisms of resistance will offer insight for the development of more advanced targeted therapies. In this review, we discuss the molecular mechanisms of resistance to third-generation EGFR inhibitors and review recent strategies for overcoming resistance, new challenges, and future development directions.

Nanogel-mediated drug delivery system for anticancer agent: pH stimuli responsive poly(ethylene glycol/acrylic acid) nanogel prepared by gamma irradiation

The popularity of nanogel as nano drug carrier lies in its adjustable physical properties, and the ability to encapsulate drug particles with improved properties is being developed to meet the diverse pH-sensitive nanogel for anticancer agent. Monitoring pH has been identified as an important diagnostic element during the treatment process. A pH-sensitive nanogel consisting of (PEG/PMAc) in the ratio of (50:50%) hasbeen cross-linkedby γ-irradiation techniques at an irradiation dose of 5 kGy. Compound 4 and its nanogel 5 were synthesized and assessed for their anticancer effects against HepG2, A549, MCF-7 and HCT-116 as dual VEGFR-2 and EGFR tyrosine kinases inhibitors. The molecular design was performed to investigate the binding mode of compound 4 with VEGFR-2 and EGFR receptors. Our compound 5 in nanogel showed enhanced anticancer activities against the four tested cancer cell lines and also showed higher inhibition activities against VEGFR-2 and EGFR^T790M kinases than the derivative 4. Finally, our derivative 4 showed good in silico calculated ADMET profile. It was expected to show good GIT absorption in human, lower CNS side effects, no hepatotoxic actions and higher acute and oral chronic toxic doses in comparing to sorafenib and erlotinib. The obtained results showed that, our compound could be useful as a template for future design, optimization, adaptation and investigation to produce more potent and selective dual VEGFR-2/EGFR^T790M inhibitors with higher anticancer activity.

Design, Synthesis, and Antitumor Activity of Erlotinib Derivatives

Nineteen erlotinib derivatives bearing different 1,2,3-triazole moieties were designed, synthesized, and evaluated for their potential against different cancer cell lines. The structures of the synthesized compounds were confirmed via¹H NMR, ¹³C NMR, and HR MS. Preliminary antitumor activity assay results suggested that some compounds showed remarkable inhibitory activity against different cancer cell lines including the corresponding drug-resistant ones. Among these compounds, 3d was the most promising one with an IC₅₀ of 7.17 ± 0.73 μM (KYSE70TR), 7.91 ± 0.61 μM (KYSE410TR), 10.02 ± 0.75 μM (KYSE450TR), 5.76 ± 0.3 3 μM (H1650TR), and 2.38 ± 0.17 μM (HCC827GR). A preliminary mechanism study suggested that compound 3d suppressed cancer cell proliferation through the EGFR-TK pathway.

Design, synthesis, in silico docking, ADMET and anticancer evaluations of thiazolidine-2,4-diones bearing heterocyclic rings as dual VEGFR-2/EGFRT790M tyrosine kinase inhibitors

Fourteen recent thiazolidine-2,4-diones bearing furan and/or thiophene heterocyclic rings have been designed, synthesized and assessed for their anticancer activities against four human tumor cell lines HepG2, A549, MCF-7 and HCT-116 targeting both VEGFR-2 and EGFR tyrosine kinases. Molecular design was carried out to investigate the binding mode of the proposed compounds with VEGFR-2 and EGFR receptors. HepG2 was the most susceptible cell line to the influence of our derivatives. Compounds 5g and 4g revealed the highest activities against HepG2 (IC₅₀ = 3.86 and 6.22 μM), A549 (IC₅₀ = 7.55 and 12.92 μM), MCF-7 (IC₅₀ = 10.65 and 10.66 μM) and HCT116 (IC₅₀ = 9.04 and 11.17 μM) tumor cell lines. Sorafenib (IC₅₀ = 4.00, 4.04, 5.58 and 5.05 μM) and elotinib (IC₅₀ = 7.73, 5.49, 8.20 and 13.91 μM) were used as reference standards. Furthermore, the most active cytotoxic compounds 4d, 4e, 4f, 4g, 5d, 5e, 5f and 5g were selected to assess their VEGFR-2 inhibitory effects. Derivatives 5g, 4g and 4f were observed to be the highest effective derivatives that inhibited VEGFR-2 at the submicromolar level (IC₅₀ = 0.080, 0.083 and 0.095 μM respectively) in comparison to sorafenib (IC₅₀ = 0.084 μM). As well, compounds 4d, 4e, 4f, 4g, 5d, 5e, 5f and 5g were additionally assessed for their inhibitory activities against mutant EGFR^T790M. Compounds 5g and 4g could interfere with the EGFR^T790M activity exhibiting stronger activities than elotinib with IC₅₀ = 0.14 and 0.23 μM respectively. Finally, our derivatives 4g, 5f and 5g showed a good in silico calculated ADMET profile. The obtained results showed that our compounds could be useful as a template for future design, optimization, adaptation and investigation to produce more potent and selective dual VEGFR-2/EGFR^T790M inhibitors with higher anticancer activity.

Development of Dual Inhibitors Targeting Epidermal Growth Factor Receptor in Cancer Therapy

Epidermal growth factor receptor (EGFR) is of great significance in mediating cell signaling transduction and tumor behaviors. Currently, third-generation inhibitors of EGFR, especially osimertinib, are at the clinical frontier for the treatment of EGFR-mutant non-small-cell lung cancer (NSCLC). Regrettably, the rapidly developing drug resistance caused by EGFR mutations and the compensatory mechanism have largely limited their clinical efficacy. Given the synergistic effect between EGFR and other compensatory targets during tumorigenesis and tumor development, EGFR dual-target inhibitors are promising for their reduced risk of drug resistance, higher efficacy, lower dosage, and fewer adverse events than those of single-target inhibitors. Hence, we present the synergistic mechanism underlying the role of EGFR dual-target inhibitors against drug resistance, their structure-activity relationships, and their therapeutic potential. Most importantly, we emphasize the optimal target combinations and design strategies for EGFR dual-target inhibitors and provide some perspectives on new challenges and future directions in this field.

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.

Synthesis and Antitumor Activity of Erlotinib Derivatives Linked With 1,2,3-Triazole

Cervical cancer is one of the most important cause of cancer-related death and presents a major public health problem in many countries. To search for more novel antitumor agents against cervical cancer, 14 erlotinib-linked 1,2,3-triazole compounds were designed, synthesized, and evaluated for their anti-tumor activity. The compounds were confirmed by ¹H NMR, ¹³C NMR, and high-resolution mass spectra (HR MS). Antitumor activity assay results indicated that six of those compounds have remarkable inhibitory activity against human cervical cancer HeLa cells in vitro, among which compound 4m was the most potent with IC₅₀ of 3.79 μM, and compounds 4k, 4i, 4l, 4d, and 4n also demonstrated remarkable antitumor activity with IC₅₀ of 3.79, 4.16, 4.36, 7.02, and 8.21 μM. We found three of the most potent compounds 4d, 4k, and 4l induced potent apoptosis and cell cycle arrest in HeLa cells, and compounds 4d and 4l significantly restrained the cell colony formation and showed moderate epidermal growth factor receptor (EGFR) inhibitory activity with IC₅₀ of 13.01 and 1.76 μM. Therefore, these experiments indicate that these erlotinib-linked 1,2,3-triazole compounds are potential to act as effective anticancer agents against cervical cancer.

Dual target inhibitors based on EGFR: Promising anticancer agents for the treatment of cancers (2017-)

The EGFR family play a significant role in cell signal transduction and their overexpression is implicated in the pathogenesis of numerous human solid cancers. Inhibition of the EGFR-mediated signaling pathways by EGFR inhibitors is a widely used strategy for the treatment of cancers. In most cases, the EGFR inhibitors used in clinic were only effective when the cancer cells harbored specific activating EGFR mutations which appeared to preserve the ligand-dependency of receptor activation but altered the pattern of downstream signaling pathways. Moreover, cancer is a kind of multifactorial disease, and therefore manipulating a single target may result in treatment failure. Although drug combinations for the treatment of cancers proved to be successful, the use of two or more drugs concurrently still was a challenge in clinical therapy owing to various dose-limiting toxicities and drug-drug interactions caused by pharmacokinetic profiles changed. Therefore, a single drug targeting two or multiple targets could serve as an effective strategy for the treatment of cancers. In recent, drugs with diverse pharmacological effects have been shown to be more advantageous than combination therapies due to their lower incidences of side effects and more resilient therapies. Accordingly, dual target-single-agent strategy has become a popular field for cancer treatment, and researchers became more and more interest in the development of novel dual-target drugs in recent years. In this review, we briefly introduce the EGFR family proteins and synergisms between EGFR and other anticancer targets, and summarizes the development of potential dual target inhibitors based on wild-type and/or mutant EGFR for the treatment of solid cancers in the past five years. Additionally, the rational design and SARs of these dual target agents are also presented in detailed, which will lay a significant foundation for the further development of novel EGFR-based dual inhibitors with excellent druggability.

The synthesis and bioactivity of pyrrolo[2,3-d]pyrimidine derivatives as tyrosine kinase inhibitors for NSCLC cells with EGFR mutations

EGFR mutations are an ongoing challenge in the treatment of NSCLC, and demand continuous updating of EGFR TKI drug candidates. Pyrrolopyrimidines are one group of versatile scaffolds suitable for tailored drug development. However not many precedents of this type of pharmacophore have been investigated in the realm of third generation of covalent EGFR-TKIs. Herein, a series of pyrrolo[2,3-d]pyrimidine derivatives able to block mutant EGFR activity in a covalent manner were synthesized, through optimized Buchwald-Hartwig C-N cross coupling reactions. Their preliminary bioactivity and corresponding inhibitory mechanistic pathways were investigated at molecular and cellular levels. Several compounds exhibited increased biological activity and enhanced selectivity compared to the control compound. Notably, compound 12i selectively inhibits HCC827 cells harboring the EGFR activating mutation with up to 493-fold increased efficacy compared to in normal HBE cells. Augmented selectivity was also confirmed by kinase enzymatic assay, with the test compound selectively inhibiting the T790 M activating mutant EGFRs (IC₅₀ values of 0.21 nM) with up to 104-fold potency compared to the wild-type EGFR (IC₅₀ values of 22 nM). Theoretical simulations provide structural evidence of selective kinase inhibitory activity. Thus, this series of pyrrolo[2,3-d]pyrimidine derivatives could serve as a starting point for the development of new EGFR-TKIs.

Discovery of Potent EGFR Inhibitors With 6-Arylureido-4-anilinoquinazoline Derivatives

According to the classical pharmacophore fusion strategy, a series of 6-arylureido-4-anilinoquinazoline derivatives ( Compounds 7a - t ) were designed, synthesized, and biologically evaluated by the standard CCK-8 method and enzyme inhibition assay. Among the title compounds, Compounds 7a , 7c , 7d , 7f , 7i , 7o , 7p , and 7q exhibited promising anti-proliferative bioactivities, especially Compound 7i , which had excellent antitumor activity against the A549, HT-29, and MCF-7 cell lines (IC₅₀ = 2.25, 1.72, and 2.81 μM, respectively) compared with gefitinib, erlotinib, and sorafenib. In addition, the enzyme activity inhibition assay indicated that the synthesized compounds had sub-micromolar inhibitory levels (IC₅₀, 11.66-867.1 nM), which was consistent with the results of the tumor cell line growth inhibition tests. By comparing the binding mechanisms of Compound 7i (17.32 nM), gefitinib (25.42 nM), and erlotinib (33.25 nM) to the EGFR, it was found that Compound 7i could extend into the effective region with a similar action conformation to that of gefitinib and interact with residues L85, D86, and R127, increasing the binding affinity of Compound 7i to the EGFR. Based on the molecular hybridization strategy, 14 compounds with EGFR inhibitory activity were designed and synthesized, and the action mechanism was explored through computational approaches, providing valuable clues for the research of antitumor agents based on EGFR inhibitors.

A study on MAPK/ERK and CDK2-Cyclin-E signal switch "on and off" in cell proliferation by bis urea derivatives of 1, 4-Diisocyanatobenzene

A series of novel substituted bisurea 1,4-Diisocyanatobenzene compounds were designed, synthesized and introduced as potent anticancer compounds and screened for their in vitro anti-proliferative activities in human cancer cell lines. The structures of all titled compounds were characterized using Fourier-transform infrared mass spectra, nuclear magnetic resonance spectroscopy, elemental analysis and evaluated their sustainability using biological experiments. A selected group of ten derivatives were apprised for their anti-proliferative activity. The compounds 3d and 3e displayed potent anticancer activity with low IC₅₀ value of 5.40, and 5.89 μM against HeLa cancer cell lines. The observed apoptosis data has demonstrated that compounds 3d and 3e induce the activaties of caspase-9 and caspase-3, the compounds 3d and 3e regulated fungal zone inhibition. Due to promising growth inhibitions, the all synthesized compounds were allowed to campaign includes quantum-polarized-ligand, quantum mechanical and molecular mechanical, docking experiments. The compounds 3d and 3e have exhibited a higher affinity for ERK/MAP kinase and CDK2 proteins. The molecular docking interactions have demonstrated two stage inhibition of cancer cells by binding with ERK/MAP kinase and CDK2 leads to inactivation of cell proliferation,cell cycle progression,cell divisionanddifferentiation, and hypo-phosphorylation of ribosome leading cells to restricts at point boundary of the G1/S phase. The long-range molecular dynamics, 150 ns, simulations were also revealed more consistency by 3d. Our study conclude good binding propensity for active-tunnel of ERK/MAP kinase and CDK2 proteins, by 3d (1,1'-(1,4-phenylene) bis(3-(2-chlorobenzyl)urea)), to suggest that the designed and synthesized 3d is to use as selective novel nuclei in anti-cancer chemotherapeutics.

Ceric ammonium nitrate (CAN) enabled concerted nitration/ureation of carbodiimides to synthesize o-nitroaryl ureas

A simple and facile strategy to construct o-nitroaryl urea employing carbodiimides and ceric ammonium nitrate (CAN) with high functional group compatibility via concerted nitration/ureation has been described.

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.

Structure-activity relationship study of novel quinazoline-based 1,6-naphthyridinones as MET inhibitors with potent antitumor efficacy

As a privileged scaffold, the quinazoline ring is widely used in the development of EGFR inhibitors, while few quinazoline-based MET inhibitors are reported. In our ongoing efforts to develop new MET-targeted anticancer drug candidates, a series of quinazoline-based 1,6-naphthyridinone derivatives were designed, synthesized, and evaluated for their biological activities. The preliminary SARs studies indicate that the quinazoline scaffold was also acceptable for the block A of class II MET inhibitors. The further pharmacokinetic studies led to the identification of the most promising compound 22a with favorable in vitro potency (MET, IC₅₀ = 9.0 nM), human microsomal metabolic stability (t_1/2 = 621.2 min) and oral bioavailability (F = 42%). Moreover, 22a displayed good in vivo antitumor efficacy (IR of 81% in 75 mg/kg) in MET-positive human glioblastoma U-87 MG xenograft model. These positive results indicated that 22a is a potential new MET-targeted antitumor drug lead, which is worthy of further development.

Design, synthesis and molecular modeling studies of 2-styrylquinazoline derivatives as EGFR inhibitors and apoptosis inducers

Herein, we report the synthesis of novel 2-substituted styrylquinazolines conjugated with aniline or sulfonamide moieties, anticipated to act as potent anticancer therapeutic agents through preferential EGFR inhibition. In doing so, all the synthesized compounds were screened for their in vitro anticancer activities (nine subpanels) at the National Cancer Institute (NCI), USA. The resulting two most active anticancer compounds (7b and 8c) were then chemically manipulated to investigate feasible derivatives (12a-e and 15a-d). MTT cytotoxicity, in vitro cell free EGFR and anti-proliferative activity against EGFR/ A549 cell line evaluation for the most active broadly spectrum candidates (7a/b, 8c/e, 12b and 15d) was conducted. Promising results were obtained for the styrylquinazoline-benzenesulfonamide derivative 8c (IC50 = 8.62 µM, 0.190 µM and = 79.25%), if compared to lapatanib (IC50 = 11.98 µM, 0.190 µM, and 79.25%), respectively. Moreover, its apoptotic induction potential was studied through cell cycle analysis, Annexin-V and caspase-3 activation assays. Results showed a clear cell arrest at G2/M phase, a late apoptotic increase (76 folds) and a fruitful caspase-3 expression change (8 folds), compared to the control. Finally, molecular docking studies of compounds 7a/b, 8c/e, 12b and 15d revealed proper fitting into the active site of EGFR with a low binding energy score for compound 8c (-13.19 Kcal/mole), compared to lapatanib (-14.54 Kcal/mole).

The new opportunities in medicinal chemistry of fourth-generation EGFR inhibitors to overcome C797S mutation

Epidermal growth factor receptor (EGFR) is a receptor for epithelial growth factor (EGF) cell proliferation and signaling, which is related to the inhibition of tumor cell proliferation, angiogenesis, tumor invasion, metastasis, and apoptosis. Thus, it has become an important target for the treatment of non-small cell lung cancer (NSCLC). The first to the third-generation EGFR inhibitors have demonstrated powerful efficacy and brought a prospect to patients. Unfortunately, after 9-15 months of treatment, they all developed resistance without exception. As for the resistance of third-generation inhibitors, no major breakthrough has been made in this field. In this review, we discussed the recent advances in medicinal chemistry of fourth-generation EGFR-TKIs, as well as further discussed the clinical challenges and future prospects of treating patients with EGFR mutations resistant to third-generation EGFR-TKIs.

Design, synthesis and antitumor activity of icotinib derivatives

EGFR-TK pathway is of high importance for the treatment of non-small-cell lung cancers (NSCLC), and it will be challenging to develop anti-tumor drugs that could inhibit both EGFR wild-type and mutant tumor cells. Here, a series of icotinib derivatives containing 1,2,3-triazole moiety were designed and synthesized through copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reactions. Preliminary CCK-8 assay showed that the prepared icotinib-1,2,3-triazole compounds such as a7 or a12 demonstrated potent in vitro antitumor activity against the NSCLC cells expressing both wild type EGFR and mutational EGFR. Further, the mechanism of action for compounds a7 and a12 induced NSCLC cells death was also detailed, and the results suggested a possible induced NSCLC cells death via inducing mitochondrial apoptosis and arresting cell cycle. Remarkably, the inhibition of EGFR by these icotinib derivatives was also studied. The results showed that compound a12 was a potent inhibitor for EGFR with IC₅₀ value of 1.49 μM. Combining these results, an EGFR inhibitor a12 represents a promising new anti-NSCLC candidate that could induce apoptosis and arrest cell cycle.

Therapeutic progression of quinazolines as targeted chemotherapeutic agents

Presently cancer is a grave health issue with predominance beyond restrictions. It can affect any organ of the body. Most of the available chemotherapeutic drugs are highly toxic, not much selective and eventually lead to the development of resistance. Therefore, a target specific palliative approach for the treatment of cancer is required. Remarkable advancements in science have illuminated various molecular pathways responsible for cancer. This has resulted in abundant opportunities to develop targeted anticancer agents. Quinazoline nucleus is a privileged scaffold with significant diversified pharmacological activities. Numerous established anticancer quinazoline derivatives constitute a new class of chemotherapeutic agents which are found to act by inhibiting various protein kinases as well as other molecular targets. A recent update on various quinazoline derivatives acting on different types of molecular targets for the treatment of cancer has been compiled in this review. Brief SAR studies of quinazoline derivatives acting through different mechanisms of action have been highlighted. The comprehensive medicinal chemistry aspects of these agents in this review provide a panoramic view to the biologists as well as medicinal chemists working in this area and would assist them in their efforts to design and synthesize novel quinazoline based anticancer compounds.

Discovery of new pyrimidine-5-carbonitrile derivatives as anticancer agents targeting EGFRWT and EGFRT790M

A new series of pyrimidine-5-carbonitrile derivatives has been designed as ATP mimicking tyrosine kinase inhibitors of the epidermal growth factor receptor (EGFR). These compounds were synthesized and evaluated for their in vitro cytotoxic activities against a panel of four human tumor cell lines, namely colorectal carcinoma (HCT-116), hepatocellular carcinoma (HepG-2), breast cancer (MCF-7), and non-small cell lung cancer cells (A549). Five of the synthesized compounds, 11a, 11b, 12b, 15b and 16a, were found to exhibit moderate antiproliferative activity against the tested cell lines and were more active than the EGFR inhibitor erlotinib. In particular, compound 11b showed 4.5- to 8.4-fold erlotinib activity against HCT-116, HepG-2, MCF-7, and A549 cells with IC50 values of 3.37, 3.04, 4.14, and 2.4 μM respectively. Moreover, the most cytotoxic compounds that showed promising IC50 values against the four cancer cell lines were subjected to further investigation for their kinase inhibitory activities against EGFRWT and EGFRT790M using homogeneous time resolved fluorescence (HTRF) assay. Compound 11b was also found to be the most active compound against both EGFRWT and mutant EGFRT790M, exhibiting IC50 values of 0.09 and 4.03 μM, respectively. The cell cycle and apoptosis analyses revealed that compound 11b can arrest the cell cycle at the G2/M phase and induce significant apoptotic effects in HCT-116, HepG-2, and MCF-7 cells. Additionally, compound 11b upregulated the level of caspase-3 by 6.5 fold in HepG-2 when compared with the control. Finally, molecular docking studies were carried out to examine the binding mode of the synthesized compounds against the proposed targets; EGFRWT and EGFRT790M. Additional in silico ADMET studies were performed to explore drug-likeness properties.

6,7-Disubstituted-4-anilinoquinazoline: Design, Synthesis and Anticancer Activity as a Novel Series of Potent Anticancer Agents

Background: Epidermal Growth Factor Receptor (EGFR) and vascular endothelial growth factor receptor (VEGFR) are responsible for several pathological conditions such as the development of different kinds of tumors. The combined inhibition of both signal transduction pathways seems to be a promising novel approach for cancer treatment. Methods: In this study, novel 4-anilinoquinazoline derivatives with various substituents on-7 position of quinazoline moiety were designed, synthesized, and evaluated for their antiproliferative activity against A431 and HU02 cell lines. Results: Compounds 8a, 8d, and 8f displayed the most potent anticancer activities against A431(IC50 = 1.78 μM, 8.25 μM, and 7.18 μM, respectively) in comparison with reference standards(erlotinib IC50=8.31 μM and vandetanib IC50=10.62 μM). Molecular docking studies proved that8a as the most potent compound could be efficiently accommodated in the ATP binding site ofEGFR and VEGFR-2 through the formation of essential hydrogen bonds between quinazolineN1 atom and the Met796 backbone of EGFR as well as the Cys919 backbone of VEGFR-2 with a distance of 1.94 Å and 1.398 Å, respectively. Conclusion: Compound 8a as the most potent compound with morpholine and 3-bromoaniline at the 7 and 4 positions of quinazoline scaffold, respectively, deserves more study and structural optimization as an anticancer agent.

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.

Urea Derivatives in Modern Drug Discovery and Medicinal Chemistry

The urea functionality is inherent to numerous bioactive compounds, including a variety of clinically approved therapies. Urea containing compounds are increasingly used in medicinal chemistry and drug design in order to establish key drug-target interactions and fine-tune crucial drug-like properties. In this perspective, we highlight physicochemical and conformational properties of urea derivatives. We provide outlines of traditional reagents and chemical procedures for the preparation of ureas. Also, we discuss newly developed methodologies mainly aimed at overcoming safety issues associated with traditional synthesis. Finally, we provide a broad overview of urea-based medicinally relevant compounds, ranging from approved drugs to recent medicinal chemistry developments.

Tanshinone IIA Reverses Gefitinib-Resistance In Human Non-Small-Cell Lung Cancer Via Regulation Of VEGFR/Akt Pathway

Background

Gefitinib-resistance is a primary obstacle for the treatment of non-small-cell lung cancer (NSCLC). It has been shown that tanshinone IIA (Tan IIA) could induce apoptosis of NSCLC cells. However, the role of combination of gefitinib with Tan IIA on gefitinib-resistance NSCLC cells remains unclear. Thus, this study aimed to investigate the role of combination on the proliferation, apoptosis and invasion of gefitinib-resistance NSCLC cells.

Methods

CCK-8, flow cytometric and transwell assays were applied to detect proliferation, apoptosis and invasion in gefitinib-resistance NSCLC cells, respectively. In addition, Western blotting assay was used to detect the expressions of p-EGFR, p-VEGFR2, and p-Akt in HCC827/gefitinib cells.

Results

In this study, Tan IIA enhanced the cytotoxic effect of gefitinib in gefitinib-resistance NSCLC cells. In addition, the inhibitory effects of gefitinib on the proliferation, migration and invasion of gefitinib-resistance NSCLC cells were enhanced in the presence of Tan IIA. Moreover, Tan IIA enhanced the pro-apoptotic effect of gefitinib in gefitinib-resistance NSCLC cells via increasing the level of cleaved caspase 3. Meanwhile, Tan IIA enhanced the sensitivity of HCC827/gefitinib cells to gefitinib via downregulation of the VEGFR2/Akt pathway. In vivo experiments further confirmed that combination of gefitinib with Tan IIA inhibited tumor growth in mouse xenograft model of HCC827/gefitinib.

Conclusion

We found that Tan IIA could enhance gefitinib sensitivity in gefitinib-resistance NSCLC cells. Therefore, combination of gefitinib with Tan IIA might be considered as a therapeutic approach for the treatment of gefitinib-resistant NSCLC.

Design, synthesis and antitumor activity of aromatic urea-quinazolines

Background: Gefitinib and sorafenib have been proved effective for the treatment of cancers in clinical practice for years. Materials & methods: We intended to integrate the structural features of gefitinib and sorafenib and construct structurally unique 7-aromatic ureido-4-anilinoquinazolines. Results: Most of the targets exhibited promising antitumor activities. 8u showed excellent antitumor activities against the three tested cell lines (IC₅₀, 0.81-2.49 μM). The enzymatic, apoptosis assay of 8u were also performed to study their preliminary action of mechanism. Conclusion: 8u deserve further research as antitumor agents.

Design, synthesis and biological evaluation of novel 4-anlinoquinazoline derivatives as EGFR inhibitors with the potential to inhibit the gefitinib-resistant nonsmall cell lung cancers

A series of quinazoline derivatives with benzylidene hydrazine carboxamide were designed and synthesised as EGFR inhibitors. Most compounds exhibited exceptional anti-proliferative activity against A549, HepG2, MCF-7 and H1975 cells. Furthermore, six compounds demonstrated excellent inhibition activity against EGFR^WT with the IC₅₀ value both less than 2 nM. Among the six compounds, 44 exhibited the strongest activity (0.4 nM) and potently inhibited EGFR^L858R/T790M (0.1 μM). Excitingly, the most potent compound 14 showed excellent enzyme inhibitory activity with 6.3 nM and 8.4 nM for both EGFR^WT and EGFR^T790M/L858R. The result of AO single staining and Annexin V/PI staining showed that the compound 14 and 44 could induce remarkable apoptosis of A549 cells. The compound 14 arrested the cell cycle at the S phase and compound 44 arrested the cell cycle at the G0 phase in A549 cells. These preliminary results demonstrate that compound 14 and 44 may be promising lead compound-targeting EGFR.