Design, synthesis, in vitro anticancer evaluation, kinase inhibitory effects, and pharmacokinetic profile of new 1,3,4-triarylpyrazole derivatives possessing terminal sulfonamide moiety

An overview of pyridazin-3(2H)-one: a core for developing bioactive agents targeting cardiovascular diseases and cancer

Cardiovascular diseases (CVDs) and cancer are the top two leading causes of death globally. Vasodilators are commonly used to treat various CVDs. In cancer treatment, targeted anticancer agents have been developed to minimize side effects compared with traditional chemotherapy. Many hypertension patients are more prone to cancer, a case known as reverse cardio-oncology. This leads to the search for drugs with dual activity or repurposing strategy to discover new therapeutic uses for known drugs. Recently, medicinal chemists have shown great interest in synthesizing pyridazinone derivatives due to their significant biological activities in tackling these critical health challenges. This review will concentrate on pyridazin-3(2H)-one-containing compounds as vasodilators and anticancer agents, along with a brief overview of various methods for their synthesis.

A comprehensive review on phosphatidylinositol-3-kinase (PI3K) and its inhibitors bearing pyrazole or indazole core for cancer therapy

Cancer is a complex and multifaceted group of diseases with a high mortality rate characterized by uncontrolled proliferation of abnormal cells. Dysregulation of normal signalling pathways in cancer contributes to the different hallmarks of this disease. The signalling pathway of which phosphatidylinositol 3-kinase (PI3K) is a part is not an exception. In fact, dysregulated activation of PI3K signalling pathways can result in unbridled cellular proliferation and enhanced cell survival, thereby fostering the onset and advancement of cancer. Therefore, there is substantial interest in developing targeted therapies specifically aimed at inhibiting the PI3K enzyme and its associated pathways. Also, the therapeutic interest on pyrazoles and indazoles has been growing due to their various medicinal properties, namely, anticancer activity. Derivatives of these compounds have been studied as PI3K inhibitors, and they showed promising results. There are already some PI3K inhibitors approved by Food and Drug Administration (FDA), such as Idelalisib (Zydelig®) and Alpelisib (Piqray®). In this context, this review aims to address the importance of PI3K in cellular processes and its role in cancer. Additionally, it aims to report a comprehensive literature review of PI3K inhibitors, containing the pyrazole and indazole scaffolds, published in the last fifteen years, focusing on structure-activity relationship aspects, thus providing important insights for the design of novel and more effective PI3K inhibitors.

Development of 1,5-diarylpyrazoles as EGFR/JNK-2 dual inhibitors: design, synthesis, moleecular docking, and bioactivity evaluation

The eradication of multifactorial diseases, such as cancer, requires the design of drug candidates that attack multiple targets that contribute to the progression and proliferation of such diseases. Here, 1,5-diarylpyrazole derivatives bearing vanillin or sulfanilamide are developed as potential dual inhibitors of epidermal growth factor receptor (EGFR)/c-Jun N-terminal kinase 2 (JNK-2) for possible anticancer activity. These derivatives inhibited the growths of DLD-1, HeLa, K-562, SUIT-2 and HepG2 cancer cell lines, with minimum concentration required to inhibit half of the cellular growth (IC50) values of 2.7-63 μM. The tests confirmed that 5b and 5d were potent JNK-2 inhibitors, with IC50 of 2.0 and 0.9 μM, respectively, whereas 6 h selectively inhibited EGFR protein kinase (EGFR-PK) (IC50 = 1.7 μM). Notably, 6c inhibited both kinases, with IC50 values of 2.7 and 3.0 μM against EGFR-PK and JNK-2, respectively, offering a reference for designing mutual inhibitors of EGFR/JNK-2. The docking studies revealed the ability of the pyrazole ring to bind to the hinge region of the ATP binding site, thereby supporting the experimental inhibitory results. Furthermore, the developed compounds could induce apoptosis and induce cell cycle arrest at different cell phases.

A review of poly(ADP-ribose)polymerase-1 (PARP1) role and its inhibitors bearing pyrazole or indazole core for cancer therapy

Cancer is a disease with a high mortality rate characterized by uncontrolled proliferation of abnormal cells. The hallmarks of cancer evidence the acquired cells characteristics that promote the growth of malignant tumours, including genomic instability and mutations, the ability to evade cellular death and the capacity of sustaining proliferative signalization. Poly(ADP-ribose) polymerase-1 (PARP1) is a protein that plays key roles in cellular regulation, namely in DNA damage repair and cell survival. The inhibition of PARP1 promotes cellular death in cells with homologous recombination deficiency, and therefore, the interest in PARP protein has been rising as a target for anticancer therapies. There are already some PARP1 inhibitors approved by Food and Drug Administration (FDA), such as Olaparib and Niraparib. The last compound presents in its structure an indazole core. In fact, pyrazoles and indazoles have been raising interest due to their various medicinal properties, namely, anticancer activity. Derivatives of these compounds have been studied as inhibitors of PARP1 and presented promising results. Therefore, this review aims to address the importance of PARP1 in cell regulation and its role in cancer. Moreover, it intends to report a comprehensive literature review of PARP1 inhibitors, containing the pyrazole and indazole scaffolds, published in the last fifteen years, focusing on structure-activity relationship aspects, thus providing important insights for the design of novel and more effective PARP1 inhibitors.

New 1,2,3-triazole/1,2,4-triazole hybrids linked to oxime moiety as nitric oxide donor selective COX-2, aromatase, B-RAFV600E and EGFR inhibitors celecoxib analogs: design, synthesis, anti-inflammatory/anti-proliferative activities, apoptosis and molecular modeling study

A new series of bis-triazole 19a-l was synthesised for the purpose of being hybrid molecules with both anti-inflammatory and anti-cancer activities and assessed for cell cycle arrest, NO release. Compounds 19c, 19f, 19h, 19 l exhibited COX-2 selectivity indexes in the range of 18.48 to 49.38 compared to celecoxib S.I. = 21.10), inhibit MCF-7 with IC50 = 9-16 μM compared to tamoxifen (IC50 = 27.9 μM). and showed good inhibitory activity against HEP-3B with IC50 = 4.5-14 μM compared to sorafenib (IC50 = 3.5 μM) (HEP-3B). Moreover, derivatives 19e, 19j, 19k, 19 l inhibit HCT-116 with IC50 = 5.3-13.7 μM compared to 5-FU with IC50 = 4.8 μM (HCT-116). Compounds 19c, 19f, 19h, 19 l showed excellent inhibitory activity against A549 with IC50 = 3-4.5 μM compared to 5-FU with IC50 = 6 μM (A549). Compounds 19c, 19f, 19h, 19 l inhibit aromatase (IC50 of 22.40, 23.20, 22.70, 30.30 μM), EGFR (IC50 of 0.112, 0.205, 0.169 and 0.066 μM) and B-RAFV600E (IC50 of 0.09, 0.06, 0.07 and 0.05 μM).

The Importance of the Pyrazole Scaffold in the Design of Protein Kinases Inhibitors as Targeted Anticancer Therapies

The altered activation or overexpression of protein kinases (PKs) is a major subject of research in oncology and their inhibition using small molecules, protein kinases inhibitors (PKI) is the best available option for the cure of cancer. The pyrazole ring is extensively employed in the field of medicinal chemistry and drug development strategies, playing a vital role as a fundamental framework in the structure of various PKIs. This scaffold holds major importance and is considered a privileged structure based on its synthetic accessibility, drug-like properties, and its versatile bioisosteric replacement function. It has proven to play a key role in many PKI, such as the inhibitors of Akt, Aurora kinases, MAPK, B-raf, JAK, Bcr-Abl, c-Met, PDGFR, FGFRT, and RET. Of the 74 small molecule PKI approved by the US FDA, 8 contain a pyrazole ring: Avapritinib, Asciminib, Crizotinib, Encorafenib, Erdafitinib, Pralsetinib, Pirtobrutinib, and Ruxolitinib. The focus of this review is on the importance of the unfused pyrazole ring within the clinically tested PKI and on the additional required elements of their chemical structures. Related important pyrazole fused scaffolds like indazole, pyrrolo[1,2-b]pyrazole, pyrazolo[4,3-b]pyridine, pyrazolo[1,5-a]pyrimidine, or pyrazolo[3,4-d]pyrimidine are beyond the subject of this work.

Transition-Metal-Free Multicomponent Approach to the Regioselective Synthesis of Highly Substituted N-Alkylpyrazoles

An efficient transition-metal-free multicomponent approach to the regioselective synthesis of highly substituted N-alkylpyrazoles through 1,6-addition of pyrazole (in situ generated from α,β-unsaturated aldehyde and hydrazide) to para-Quinone Methides has been developed. The N-alkylpyrazole containing triarylmethanes having several heteroaryl rings (quinoline, pyridine, thiophene) at the central methine carbon atom was developed. This chemical process may be used for large-scale synthesis and provides a novel way to produce triarylmethanes with diverse functional groups.

Design and synthesis of new adamantyl derivatives as promising antiproliferative agents

A series of adamantyl carboxamide derivatives containing sulfonate or sulfonamide moiety were designed as multitargeted inhibitors of ectonucleotide pyrophosphatases/phosphodiesterases (NPPs) and carbonic anhydrases (CAs). The target compounds were investigated for their antiproliferative activity against NCI-60 cancer cell lines panel. Three main series composed of 3- and 4-aminophenol, 4-aminoaniline, and 5-hydroxyindole scaffolds were designed based on a lead compound (A). Compounds 1e (benzenesulfonyl) and 1i (4-fluorobenzenesulfonyl) of 4-aminophenol backbone exhibited the most promising antiproliferative activity. Both compounds exhibited a broad-spectrum and potent inhibition against all the nine tested cancer subtypes. Both compounds showed nanomolar IC50 values over several cancer cell lines that belong to leukemia and colon cancer such as K-562, RPMI-8226, SR, COLO 205, HCT-116, HCT-15, HT29, KM12, and SW-620 cell lines. Compounds 1e and 1i induced apoptosis in K-562 leukemia cells in a dose-dependent manner. Compound 1i showed the highest cytotoxic activity with IC50 value of 200 nM against HT29 cell line. In addition, compounds 1e and 1i were tested against normal breast cells (HME1) and normal skin fibroblast cells (F180) and the results revealed that the compounds are safe toward normal cells compared to cancers cells. Enzymatic assays against NPP1-3 and carbonic anhydrases II, IX, and XII were performed to investigate the possible molecular target(s) of compounds 1e and 1i. Furthermore, a molecular docking study was performed to predict the binding modes of compounds 1e and 1i in the active site of the most sensitive enzymes subtypes.

Evaluation of Substituted Pyrazole-Based Kinase Inhibitors in One Decade (2011-2020): Current Status and Future Prospects

Pyrazole has been recognized as a pharmacologically important privileged scaffold whose derivatives produce almost all types of pharmacological activities and have attracted much attention in the last decades. Of the various pyrazole derivatives reported as potential therapeutic agents, this article focuses on pyrazole-based kinase inhibitors. Pyrazole-possessing kinase inhibitors play a crucial role in various disease areas, especially in many cancer types such as lymphoma, breast cancer, melanoma, cervical cancer, and others in addition to inflammation and neurodegenerative disorders. In this article, we reviewed the structural and biological characteristics of the pyrazole derivatives recently reported as kinase inhibitors and classified them according to their target kinases in a chronological order. We reviewed the reports including pyrazole derivatives as kinase inhibitors published during the past decade (2011-2020).

Anticancer profile and anti-inflammatory effect of new N-(2-((4-(1,3-diphenyl-1H-pyrazol-4-yl)pyridine sulfonamide derivatives

A new series of N-(2-((4-(1,3-diphenyl-1H-pyrazol-4-yl)pyridine sulfonamide derivatives 11a-o were designed and synthesized based on our previous works. The new series was tested for its anticancer and anti-inflammatory effects. The anticancer profile of final target compounds was obtained by testing them over 60 cell lines belong to nine types of cancers. Compound 11c showed the highest percent inhibition, so its potency was measured over the most sensitive cell line to determine its IC₅₀ over each cell. In addition, compound 11c was tested over kinase panel to get its biological target(s). Compound 11c had strong activity over JNK1, JNK2, p38a and V600EBRAF. All final target compounds were tested against the four kinases to build a structure activity relationship. Compound 11c was subjected to cell cycle analysis to check at which phase is affected by 11c. The anti-inflammatory effect of final target compounds was screened by testing their ability to inhibit both nitric oxide release and prostaglandin E2 production on raw 264.7 macrophages in addition to test their cytotoxic effect on the same cells. Compound 11n showed the highest ability to inhibit prostaglandin E2 and all compound showed moderate to low activity regarding inhibition of nitric oxide release. Compound 11n was investigated for its ability to reduce Interleukin 6 and TNF-alpha. In addition, compound 11n was tested for its effect on induced Nitric oxide synthase (iNOS), and COX-2 mRNA expression level and its effect on nitric oxide synthase (iNOS), COX-1 and COX-2 protein levels where it showed selectivity for COX-2 compared to COX-1 and iNOS.

Recent developments in mitogen activated protein kinase inhibitors as potential anticancer agents

The mitogen activated protein kinase (MAPK) belongs to group of kinase that links the extracellular stimuli to intracellular response. The MAPK signalling pathway (RAS-RAF-MEK-ERK) involved in different pathological conditions like cancer, caused due to genetic or any other factor such as physical or environmental. Many studies have been conducted on the pathological view of MAPK cascade and its associated element like RAS, RAF, MEK, ERK or its isoforms, and still the research is going on particularly with respect to its activation, regulation and inhibition. The MAPK signalling pathway has become the area of research to identify new target for the management of cancer. A number of heterocyclics are key to fight with the cancer associated with these enzymes thus give some hope in the management of cancer by inhibiting MAPK cascade. In the present article, we have focussed on MAPK signalling pathway and role of different heterocyclic scaffolds bearing nitrogen, sulphur and oxygen and about their potential to block MAPK signalling pathway. The heterocyclics are gaining importance due to high potency and selectivity with less off-target effects against different targets involved in the MAPK signalling pathway. We have tried to cover recent advancements in the MAPK signalling pathway inhibitors with an aim to get better understanding of the mechanism of action of the compounds. Several compounds in the preclinical and clinical studies have been thoroughly dealt with. In addition to the synthetic compounds, a significant number of natural products containing heterocyclic moieties as MAPK signalling pathway inhibitors have been put together. The structure activity relationship along with docking studies have been discussed to apprehend the mechanistic studies of various compounds that will ultimately help to design and develop more MAPK signalling pathway inhibitors.

Imidazothiazole-based potent inhibitors of V600E-B-RAF kinase with promising anti-melanoma activity: biological and computational studies

A series of imidazothiazole derivatives possessing potential activity against melanoma cells were investigated for molecular mechanism of action. The target compounds were tested against V600E-B-RAF and RAF1 kinases. Compound 1zb is the most potent against both kinases with IC₅₀ values 0.978 and 8.2 nM, respectively. It showed relative selectivity against V600E mutant B-RAF kinase. Compound 1zb was also tested against four melanoma cell lines and exerted superior potency (IC₅₀ 0.18-0.59 µM) compared to the reference standard drug, sorafenib (IC₅₀ 1.95-5.45 µM). Compound 1zb demonstrated also prominent selectivity towards melanoma cells than normal skin cells. It was further tested in whole-cell kinase assay and showed in-cell V600E-B-RAF kinase inhibition with IC₅₀ of 0.19 µM. Compound 1zb induces apoptosis not necrosis in the most sensitive melanoma cell line, UACC-62. Furthermore, molecular dynamic and 3D-QSAR studies were done to investigate the binding mode and understand the pharmacophoric features of this series of compounds.

Styrylpyrazoles: Properties, Synthesis and Transformations

The pyrazole nucleus and its reduced forms, pyrazolines and pyrazolidine, are privileged scaffolds in medicinal chemistry due to their remarkable biological activities. A huge number of pyrazole derivatives have been studied and reported over time. This review article gives an overview of pyrazole derivatives that contain a styryl (2-arylvinyl) group linked in different positions of the pyrazole backbone. Although there are studies on the synthesis of styrylpyrazoles dating back to the 1970s and even earlier, this type of compound has rarely been studied. This timely review intends to summarize the properties, biological activity, methods of synthesis and transformation of styrylpyrazoles; thus, highlighting the interest and huge potential for application of this kind of compound.

Systemic review on B-RafV600E mutation as potential therapeutic target for the treatment of cancer

Cancer is one of the major public catastrophes worldwide and as per WHO, cancer is the leading cause of death universally after CVS disorders accounting for 9.6 million deaths in 2018. WHO statistics revealed five dangerous types of cancer viz. lung, breast, colorectal, prostate and skin. In male, lung cancer causes highest death, while in female, breast cancer causes the most. Alteration in MAPK signalling pathway plays a significant role in majority of cancer cases. Raf protein is activated by phosphorylation via downstream regulation of the MAPK pathway. Raf composed of 3 subtypes, viz. A-Raf, B-Raf, and C-Raf. B-Raf kinase plays a significant role in healthy cell growth in the MAPK pathway and the problem associated with B-Raf mutation leads to the development of cancer and other diseases. The progression of mutant B-Raf (B-Raf^V600E) protein is higher in cancer as compare to other diseases. In 2002, B-Raf^V600E mutation was identified for the first time in the development of cancer. The frequency of B-Raf^V600E mutation is higher in melanoma, thyroid, colorectal and ovarian cancer. We have covered small molecule B-Raf^V600E inhibitors reported in various literatures; from 2002 to 2020 and also covered clinical trial data. To widen the scope of readers, we compiled details of small molecules, specifically inhibiting B-Raf^V600E mutant and showing anti-proliferative activity against various cancer cell lines along with in-vivo data. We believe that the information covered here will be important in signifying the potentials of B-Raf^V600E mutation and its inhibitors as potent anticancer agents.

Pyrazoles as Key Scaffolds for the Development of Fluorine-18-Labeled Radiotracers for Positron Emission Tomography (PET)

The need for increasingly personalized medicine solutions (precision medicine) and quality medical treatments, has led to a growing demand and research for image-guided therapeutic solutions. Positron emission tomography (PET) is a powerful imaging technique that can be established using complementary imaging systems and selective imaging agents—chemical probes or radiotracers—which are drugs labeled with a radionuclide, also called radiopharmaceuticals. PET has two complementary purposes: selective imaging for diagnosis and monitoring of disease progression and response to treatment. The development of selective imaging agents is a growing research area, with a high number of diverse drugs, labeled with different radionuclides, being reported nowadays. This review article is focused on the use of pyrazoles as suitable scaffolds for the development of ¹⁸F-labeled radiotracers for PET imaging. A brief introduction to PET and pyrazoles, as key scaffolds in medicinal chemistry, is presented, followed by a description of the most important [¹⁸F]pyrazole-derived radiotracers (PET tracers) that have been developed in the last 20 years for selective PET imaging, grouped according to their specific targets.