Rational Design, Synthesis and Biological Evaluation of Novel Pyrazoline-Based Antiproliferative Agents in MCF-7 Cancer Cells

Insight into the therapeutic potential of pyrazole-thiazole hybrids: A comprehensive review

Several pyrazole-thiazole hybrids featuring two potentially bioactive pharmacophores with or without linker have been synthesized using the molecular hybridization approach as target structures by medicinal chemists to modulate multiple drug targets simultaneously. The presented review aims to provide an overview of the diversified and wide array of pharmacological activities of these hybrids bestowing anticancer, antifungal, antibacterial, analgesic, anti-inflammatory, antioxidant, antitubercular, antiviral, antiparasitic, and miscellaneous activities. The structure-activity relationships and potential mechanism of action are also reviewed to shed light on the development of more effective and biotargeted candidates. This review focuses on the latest research advances in the biological profile of pyrazole-thiazole hybrids reported from 2015 to the present, providing medicinal researchers with a comprehensive platform to rationally design and develop more promising pyrazole-thiazole hybrids.

Pyrazolines inhibiting the activity of the early growth response-1 DNA-binding domain

To identify compounds inhibiting the activity of the Early Growth Response (EGR)-1 DNA-binding domain, thirty-seven pyrazolines were prepared and their EGR-1 DNA-binding activities were measured. Pharmacophores were derived based on quantitative structure-activity relationship calculations. As compound 2, 1-(5-(4-methoxyphenyl)-4,5-dihydro-1H-pyrazol-3-yl)naphthalen-2-ol, showed the best inhibitory effects against the activity of the EGR-1 DNA-binding domain, the binding mode between compound 2 and EGR-1 was elucidated using in silico docking. The pharmacophores were matched to the binding modes. Electrophoretic mobility shift assays confirmed that compound 2 dose-dependently inhibited TNFα-induced EGR-1-DNA complex formation in HaCaT cells. Reverse transcription-polymerase chain reaction demonstrated that compound 2 effectively reduced the mRNA expression of EGR-1-regulated inflammatory genes, including thymic stromal lymphopoietin (TSLP), interleukin (IL)-1β, IL-6, and IL-31, in TNFα-stimulated HaCaT cells. Therefore, compound 2 could be developed as an agent that inhibits the activity of the EGR-1 DNA-binding domain.

Development in the Synthesis of Bioactive Thiazole-Based Heterocyclic Hybrids Utilizing Phenacyl Bromide

Heterocyclic hybrid frameworks represent a burgeoning domain within the realms of drug discovery and medicinal chemistry, attracting considerable attention in recent years. Thiazole pharmacophore fragments, inherent in natural products such as peptide alkaloids, metabolites, and cyclopeptides, have demonstrated a broad spectrum of pharmacological potentials. Given their profound biological significance, a plethora of thiazole-based hybrids have been synthesized through the conjugation of thiazole moieties with bioactive pyrazole and pyrazoline fragments. This review systematically presents a compendium of robust methodologies for the synthesis of thiazole-linked hybrids, employing the (3 + 2) heterocyclization reaction, specifically the Hantzsch-thiazole synthesis, utilizing phenacyl bromide as the substrate. The strategic approach of molecular hybridization has markedly enhanced drug efficacy, mitigated resistance to multiple drugs, and minimized toxicity concerns. The resultant thiazole-linked hybrids exhibit a myriad of medicinal properties viz. anticancer, antibacterial, anticonvulsant, antifungal, antiviral, and antioxidant activities. This compilation of methodologies and insights serves as a valuable resource for medicinal chemists and researchers engaged in the design of novel thiazole-linked hybrids endowed with therapeutic attribute.

New pyrazolyl-thiazolidinone/thiazole derivatives as celecoxib/dasatinib analogues with selective COX-2, HER-2 and EGFR inhibitory effects: design, synthesis, anti-inflammatory/anti-proliferative activities, apoptosis, molecular modelling and ADME studies

Two new series of pyrazolyl-thiazolidinone/thiazole derivatives 16a-b and 18a-j were synthesised, merging the scaffolds of celecoxib and dasatinib. Compounds 16a, 16b and 18f inhibit COX-2 with S.I. 134.6, 26.08 and 42.13 respectively (celecoxib S.I. = 24.09). Compounds 16a, 16b, 18c, 18d and 18f inhibit MCF-7 with IC50 = 0.73-6.25 μM (dasatinib IC50 = 7.99 μM) and (doxorubicin IC50 = 3.1 μM) and inhibit A549 with IC50 = 1.64-14.3 μM (dasatinib IC50 = 11.8 μM and doxorubicin IC50 = 2.42 μM) with S.I. (F180/MCF7) of 33.15, 7.13, 18.72, 13.25 and 8.28 respectively higher than dasatinib (4.03) and doxorubicin (3.02) and S.I. (F180/A549) of 14.75, 12.96, 4.16, 7.07 and 18.88 respectively higher than that of dasatinib (S.I. = 2.72) and doxorubicin (S.I = 3.88). Derivatives 16a, 18c, 18d, 18f inhibit EGFR and HER-2 IC50 for EGFR of 0.043, 0.226, 0.388, 0.19 μM respectively and for HER-2 of 0.032, 0.144, 0.195, 0.201 μM respectively.

New Thiazolyl-Pyrazoline Derivatives as Potential Dual EGFR/HER2 Inhibitors: Design, Synthesis, Anticancer Activity Evaluation and In Silico Study

A new series of thiazolyl-pyrazoline derivatives (4a-d, 5a-d 6a, b, 7a-d, 8a, b, and 10a, b) have been designed and synthesized through the combination of thiazole and pyrazoline moieties, starting from the key building blocks pyrazoline carbothioamides (1a-b). These eighteen derivatives have been designed as anticipated EGFR/HER2 dual inhibitors. The efficacy of the developed compounds in inhibiting cell proliferation was assessed using the breast cancer MCF-7 cell line. Among the new synthesized thiazolyl-pyrazolines, compounds 6a, 6b, 10a, and 10b displayed potent anticancer activity toward MCF-7 with IC50 = 4.08, 5.64, 3.37, and 3.54 µM, respectively, when compared with lapatinib (IC50 = 5.88 µM). In addition, enzymatic assays were also run for the most cytotoxic compounds (6a and 6b) toward EGFR and HER2 to demonstrate their dual inhibitory activity. They revealed promising inhibition potency against EGFR with IC50 = 0.024, and 0.005 µM, respectively, whereas their IC50 = 0.047 and 0.022 µM toward HER2, respectively, compared with lapatinib (IC50 = 0.007 and 0.018 µM). Both compounds 6a and 10a induced apoptosis by arresting the cell cycle of the MCF-7 cell line at the G1 and G1/S phases, respectively. Molecular modeling studies for the promising candidates 6a and 10a showed that they formed the essential binding with the crucial amino acids for EGFR and HER2 inhibition, supporting the in vitro assay results. Furthermore, ADMET study predictions were carried out for the compounds in the study.

Synthesis and Anticancer Activities of Pyrazole-Thiadiazole-Based EGFR Inhibitors

Lung cancer is one of the most common cancer types of cancer with the highest mortality rates. However, while epidermal growth factor receptor (EGFR) is an important parameter for lung cancer, EGFR inhibitors also show great promise in the treatment of the disease. Therefore, a series of new EGFR inhibitor candidates containing thiadiazole and pyrazole rings have been developed. The activities of the synthesized compounds were elucidated by in vitro MTT, (which is chemically 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), cytotoxicity assay, analysis of mitochondrial membrane potential (MMP) by flow cytometry, and EGFR inhibition experiments. Molecular docking and molecular dynamics simulations were performed as in silico studies. Compounds 6d, 6g, and 6j showed inhibitor activity against the A549 cell line with IC50 = 5.176 ± 0.164; 1.537 ± 0.097; and 8.493 ± 0.667 μM values, respectively. As a result of MMP by flow cytometry, compound 6g showed 80.93% mitochondrial membrane potential. According to the results of the obtained EGFR inhibitory assay, compound 6g shows inhibitory activity on the EGFR enzyme with a value of IC50 = 0.024 ± 0.002 μM.

Current scenario of pyrazole hybrids with in vivo therapeutic potential against cancers

Chemotherapeutics occupy a pivotal role in the medication of different types of cancers, but the prevalence and mortality rates of cancer remain high. The drug resistance and low specificity of current available chemotherapeutics are the main barriers for the effective cancer chemotherapy, evoking an immediate need for the development of novel anticancer agents. Pyrazole is a highly versatile five-membered heterocycle with two adjacent nitrogen atoms and possesses remarkable therapeutic effects and robust pharmacological potency. The pyrazole derivatives especially pyrazole hybrids have demonstrated potent in vitro and in vivo efficacies against cancers through multiple mechanisms, inclusive of apoptosis induction, autophagy regulation, and cell cycle disruption. Moreover, several pyrazole hybrids such as crizotanib (pyrazole-pyridine hybrid), erdafitinib (pyrazole-quinoxaline hybrid) and ruxolitinib (pyrazole-pyrrolo [2,3-d]pyrimidine hybrid) have already been approved for the cancer therapy, revealing that pyrazole hybrids are useful scaffolds to develop novel anticancer agents. The purpose of this review is to summarize the current scenario of pyrazole hybrids with potential in vivo anticancer efficacy along with mechanisms of action, toxicity, and pharmacokinetics, covering papers published in recent 5 years (2018-present), to facilitate further rational exploitation of more effective candidates.