Journal of Medicinal Chemistry最新文献

The emerging data compiled during the past five years on 3-deazaneplanocin (DZNep) provide compelling evidence to reevaluate this drug as a better alternative over the specific catalytic inhibitors of histone methyl transferases (HTMs). The indirect mechanism of DZNep via inhibition of AdoHcy-ase, once considered a liability due to possible side effects, has now shown to be rather beneficial as additional pathways targeted by DZNep are important contributors to its superior anticancer properties. Furthermore, DZNep has demonstrated the ability to induce proteasomal degradation of its target and reduce toxicity in combination with well-established antitumor therapies in animal models. In addition, DZNep has shown important effects in suppressing fibrosis and inflammation in liver, kidney, peritoneum, and airways. Finally, inhibition of mRNA m⁶A methylation by DZNep suppresses the synthesis of the viral genome in SARS-Cov-2 infection and promises to have important therapeutic value when combined with its potent antiviral efficacy and anti-inflammatory effects.

Ecto-5-nucleotidase (CD73) is overexpressed in a variety of cancers and associated with the immunosuppressive tumor microenvironment, making it an attractive target for cancer immunotherapy. Herein, we designed and synthesized a series of novel (pyridazine-3-yl)pyrimidine-2,4(1H,3H)-dione derivatives as CD73 inhibitors. These compounds exhibited remarkable inhibitory activity against CD73 in both enzymatic biochemical and cellular assays. Among them, compound 35j proved to be one of the most potent inhibitors and an uncompetitive inhibitor with no obvious cytotoxicity. This compound showed high metabolic stability in rat liver microsomes and favorable pharmacokinetic profiles in rats (T_1/2 = 3.37 h, F = 50.24%). Importantly, orally administered 35j significantly inhibited tumor growth in the triple-negative breast cancer 4T1 mouse model (TGI = 73.6%, 50 mg/kg). Immunoassays suggested that 35j remarkably increased the infiltration of positive immune cells, thereby reinvigorating antitumor immunity. These results demonstrate that 35j is a potent CD73 inhibitor worthy of further development.

Chronic kidney disease (CKD) is a condition characterized by functional deterioration with sustained inflammation and progressive fibrosis of the kidneys affecting over 800 million people worldwide. The P2X7 receptor (P2X7R) plays a key role in CKD progression. Our previous P2X7R antagonists demonstrated good efficacy for treating kidney injury but were limited by low oral exposure and short half-life, restricting their application. This study reports the optimization of P2X7R antagonists for better oral pharmacokinetics. The candidate compound 13a with the respective IC₅₀ of 34.86 and 25.28 nM against human and murine P2X7R, administered orally at 10 mg/kg in mice, exhibits a remarkably long half-life of 161.64 h, with a high exposure of 1,163,980.55 μg·h/L. Oral administration of 13a (0.3 or 1.0 mg/kg, twice weekly) significantly reduced renal injury and fibrosis in unilateral ureteral obstruction and adenine diet-induced mice models, highlighting its potential for delaying the progression of CKD.

The permeability glycoprotein, encoded by the ABCB1 gene, is widely implicated in multidrug resistance (MDR), as it has been shown to reduce the intracellular concentration of most small molecule therapeutics, including the majority of the breakpoint cluster region Abelson proto-oncogene 1 (BCR-ABL1) kinase inhibitors used in the treatment of Philadelphia chromosome positive (Ph+) leukemias. With this in mind, we describe an integrated theoretical and experimental approach to shed light on substituent effects in the pendant anilino moiety of 4-anilinoquinazolines and 4-anilinoquinoline-3-carbonitrile-based kinase inhibitors and their influence on P-gp-mediated efflux. This analysis culminated in the identification of a hydroxylamine-bearing, dual cSRC/BCR-ABL1 kinase inhibitor 16a that exhibits a marked reduction in P-gp-mediated efflux ratio and potent activity in a Ph+ patient-derived cell line (K562) and an MDR-Ph+ patient-derived cell line (K562/Dox) overexpressing P-gp. Overall, we demonstrate that the P-gp-mediated efflux ratio can be minimized by computationally driven optimization of the molecular dipole and/or cpK_a without recourse to intramolecular hydrogen bonds.

Inhibition of the receptor tyrosine kinase MerTK by small molecules has the potential to augment the immune response to tumors. Potent, selective inhibitors with high levels of in vivo target engagement are needed to fully evaluate the potential use of MerTK inhibitors as cancer therapeutics. We report the discovery and optimization of a series of pyrazinamide-based type 1.5 MerTK inhibitors bearing an azetidine-benzoxazole substituent. Compound 31 potently engages the target in vivo and demonstrates single agent activity in the immune-driven MC-38 murine syngeneic tumor model.

In this work, we have synthesized a set of peptoid-based histone deacetylase inhibitors (HDACi) with a substituted hydrazide moiety as zinc-binding group. Subsequently, all compounds were evaluated in biochemical HDAC inhibition assays and for their antiproliferative activity against native and cisplatin-resistant cancer cell lines. The hydrazide derivatives with a propyl or butyl substituent (compounds 5 and 6) emerged as the most potent class I HDAC selective inhibitors (HDAC1-3). Further, compounds 5 and 6 outperformed entinostat in cytotoxicity assays and were able to reverse chemoresistance in cisplatin-resistant A2780 (ovarian) and Cal27 (head-neck) cancer cell lines. Moreover, the hydrazide derivatives 5 and 6 showed strong synergism with cisplatin (combination indices <0.2), again outperforming entinostat, and increased DNA damage, p21, and pro-apoptotic BIM expression, leading to caspase-mediated apoptosis and cell death. Thus, compounds 5 and 6 represent promising lead structures for developing new HDACi capable of reversing chemoresistance in cisplatin resistant cancer cells.