Sunday, March 22, 2026

Covalent JAK3 inhibitors based on 2-arylamino and 7H-pyrrolo[2,3-d]pyrimidine scaffold: design, synthesis, and biological evaluation for the potential treatment of Bortezomib-resistant multiple myeloma

Tian, L.; Li, J.; Yu, J.; Han, Q.; Bolghanabadi, N.; Wang, K.; Chen, Z.; Zheng, X.; Chu, P.; Chen, L.

Euro J Med Chem, 2026

DOI: https://doi.org/10.1016/j.ejmech.2026.118764

Bortezomib, as a first-generation proteasome inhibitor, is one of the cornerstone drugs in the treatment of multiple myeloma. However, its long-term clinical efficacy is severely limited by both primary and acquired resistance. Studies have shown that the Janus kinase 3/Signal transducer and activator of transcription (JAK/STAT) signaling pathway may be persistently activated in certain bortezomib-resistant myeloma cells. Herein, we designed, synthesized, and evaluated a series of acrylamide group-bearing 2-arylaminopyrimidine derivatives as potent Janus kinase 3 (JAK3) inhibitors. Among them, 7n, a promising compound, exhibited a strong combining capability with JAK3 (half-maximal inhibitory concentration [IC50] = 0.7473 nM) and effective antiproliferative activities against Bortezomib-resistant KM3 cells (IC50 = 0.2452 μM). The results of the pharmacokinetics analysis showed that 7n presented good oral bioavailability with an F value of 39.11%. Furthermore, 7n showed notable inhibition of tumor growth in a murine Bortezomib-resistant KM3 cell xenograft model. Additionally, the analysis of the mechanism of action validated that compound 7n inhibited cell migration, promoted cell apoptosis and arrested the JAK–signal transducers and activators of the transcription pathway. Notably, 7n displayed the strongest inhibitory activities against JAK3 in 76 kinase profiles with the inhibitory rate of 96.87% at the concentration of 5 nM. Altogether, these findings suggest that JAK3 is a potential target to develop the inhibitor for treating Bortezomib-resistant multiple myeloma and 7n can be considered a promising candidate for further research.

A Fragment Screen Identifies Acrylamide Covalent Inhibitors of the TEAD•YAP Protein-Protein Interaction

Khuchtumur Bum-Erdene, Mona K. Ghozayel, Mark J. Zhang, Giovanni Gonzalez-Gutierrez, Samy O. Meroueh bioRxiv 2026.03.18.712694;  doi: https...