(Phenylamino)pyrimidine-1,2,3-triazole derivatives as analogs of imatinib: searching for novel compounds against chronic myeloid leukemia

Pyrimidine: A Privileged Scaffold for the Development of Anticancer Agents as Protein Kinase Inhibitors (Recent Update)

The pyrimidine nucleus is a fundamental component of human DNA and RNA, as well as the backbone of many therapeutic agents. Its significance in medicinal chemistry is well-established, with pyrimidine derivatives receiving considerable attention due to their potent anticancer properties across various cancer cell lines. Numerous derivatives have been synthesized, drawing structural inspiration from known anticancer agents like dihydropyrimidine compounds, which include the active cores of drugs such as 5-fluorouracil and monastrol, both of which have demonstrated strong anticancer efficacy. Additionally, various pyrimidine derivatives have been developed through different synthetic pathways, exhibiting promising anticancer potential. In response to the growing need for effective cancer treatments, recent efforts have focused on synthesizing and exploring novel pyrimidine derivatives with improved efficacy and specificity. This review aims to highlight the versatility of pyrimidine-based compounds in cancer therapy, emphasizing not only their potency and binding affinity but also their optimal interaction with diverse biological targets. The goal is to facilitate the design of new pyrimidine derivatives with enhanced anticancer potential, providing effective solutions for the treatment of various cancer types.

A novel imatinib analogue inhibitor of chronic myeloid leukaemia: design, synthesis and characterization-explanation of its folded conformation

Chronic myeloid leukaemia (CML) is primarily treated using imatinib mesylate, a tyrosine kinase inhibitor (TKI) targeting the BCR::ABL1 oncoprotein. However, the development of drug resistance and adverse side effects necessitate the exploration of alternative therapeutic agents. This study presents the synthesis and characterization of a novel imatinib analogue, 3-chloro-N-(2-methyl-5-((4-(pyridin-2-yl)pyrimidin-2-yl)amino)phenyl)benzamide (PAPP1). The compound's structure was elucidated using X-ray crystallography and spectroscopic techniques, including NMR, infrared and UV-visible. Crystallographic analysis reveals that PAPP1 consists of a phenyl-amino-pyridine-pyrimidine (PAPP) scaffold with substituted aromatic rings forming a nearly coplanar geometry. Additionally, supramolecular interactions in the crystal are mediated by hydrogen bonds and dispersion forces, forming dimers and layered structures. Molecular docking studies demonstrate strong binding affinity to the ABL1 enzyme, with PAPP1 showing comparable binding energy to imatinib, indicating its potential as a lead compound for further development. Computational studies, including molecular electrostatic potential and vibrational analysis, provide further support for the structural stability and bioactivity of PAPP1. These findings suggest that PAPP could be a promising scaffold for future CML drug design, offering a potential alternative to existing TKIs, and PAPP1 is a promising lead susceptible to optimization.

Hybrids of Imatinib with Quinoline: Synthesis, Antimyeloproliferative Activity Evaluation, and Molecular Docking

Imatinib (IMT) is the first-in-class BCR-ABL commercial tyrosine kinase inhibitor (TKI). However, the resistance and toxicity associated with the use of IMT highlight the importance of the search for new TKIs. In this context, heterocyclic systems, such as quinoline, which is present as a pharmacophore in the structure of the TKI inhibitor bosutinib (BST), have been widely applied. Thus, this work aimed to obtain new hybrids of imatinib containing quinoline moieties and evaluate them against K562 cells. The compounds were synthesized with a high purity degree. Among the produced molecules, the inhibitor 4-methyl-N3-(4-(pyridin-3-yl)pyrimidin-2-yl)-N1-(quinolin-4-yl)benzene-1,3-diamine (2g) showed a suitable reduction in cell viability, with a CC₅₀ value of 0.9 µM (IMT, CC₅₀ = 0.08 µM). Molecular docking results suggest that the interaction between the most active inhibitor 2g and the BCR-ABL1 enzyme occurs at the bosutinib binding site through a competitive inhibition mechanism. Despite being less potent and selective than IMT, 2g is a suitable prototype for use in the search for new drugs against chronic myeloid leukemia (CML), especially in patients with acquired resistance to IMT.

New Imatinib Derivatives with Antiproliferative Activity against A549 and K562 Cancer Cells

Tyrosine kinase enzymes are among the primary molecular targets for the treatment of some human neoplasms, such as those in lung cancer and chronic myeloid leukemia. Mutations in the enzyme domain can cause resistance and new inhibitors capable of circumventing these mutations are highly desired. The objective of this work was to synthesize and evaluate the antiproliferative ability of ten new analogs that contain isatins and the phenylamino-pyrimidine pyridine (PAPP) skeleton, the main pharmacophore group of imatinib. The 1,2,3-triazole core was used as a spacer in the derivatives through a click chemistry reaction and gave good yields. All the analogs were tested against A549 and K562 cells, lung cancer and chronic myeloid leukemia (CML) cell lines, respectively. In A549 cells, the 3,3-difluorinated compound (3a), the 5-chloro-3,3-difluorinated compound (3c) and the 5-bromo-3,3-difluorinated compound (3d) showed IC₅₀ values of 7.2, 6.4, and 7.3 μM, respectively, and were all more potent than imatinib (IC₅₀ of 65.4 μM). In K562 cells, the 3,3-difluoro-5-methylated compound (3b) decreased cell viability to 57.5% and, at 10 µM, showed an IC₅₀ value of 35.8 μM (imatinib, IC₅₀ = 0.08 μM). The results suggest that 3a, 3c, and 3d can be used as prototypes for the development of more potent and selective derivatives against lung cancer.