This study aimed to develop dual-target inhibitors against Aurora A and HDACs, and identified Z20 as the optimal candidate via in vitro screening. Z20 showed non-selective HDAC inhibitory activity and potent anti-tumor effects, significantly inhibiting the growth of 5 tumor cell lines (including Jurkat, HCT116) with efficacy superior to positive control CAM2602. It dose-dependently induced apoptosis and G2/M phase arrest in Jurkat and HCT116 cells, and specifically regulated the Aurora A/HDAC pathway by downregulating p-Aurora A and upregulating HDAC substrates Ac-H3/Ac-α-tubulin. However, Z20 exhibited poor in vivo efficacy (TGI: 47.2% vs. 62.7% for CAM2602) in NOG mice bearing Jurkat xenografts. Metabolic and pharmacokinetic evaluations revealed that Z20 had unfavorable properties: extremely short half-life (17.6 min), high intrinsic clearance (0.08 mL min-1 mg-1), and low oral bioavailability (0.3%), which accounted for its suboptimal in vivo performance. In conclusion, Z20 is a potent Aurora A/HDAC dual-target inhibitor in vitro, while its pharmacokinetic defects limit clinical potential. This study highlights the necessity of optimizing pharmacokinetic profiles for translating in vitro potency to in vivo efficacy.
Lirong Zhang, Xuewen Zhang, Jie Zhong et al.· RSC Medicinal Chemistry· 0 citations
The COVID-19 pandemic severely threatened global public health, and the SARS-CoV-2 main protease (3CLpro) is a vital target for anti-COVID-19 drug development. Nevertheless, most reported 3CLpro orthosteric inhibitors readily trigger viral drug resistance, limiting their long-term clinical application. Herein, we identified a novel 3CLpro allosteric site AS1 via AlloSite and AlloReverse tools. Through virtual screening and structural optimization, a series of potent 3CLpro allosteric derivatives were designed and synthesized. FRET assays confirmed that derivatives E42 (IC50 = 59.85 ± 4.10 μM) and E60 (IC50 = 7.64 ± 0.25 μM) possessed superior inhibitory potency to the lead compound E0. Structure-activity relationship and molecular docking analyses revealed that the p-trifluoromethylphenethylamine fragment, trimethylene linker, amide bond, methyl group and 4-nitropyrazole ring are key active structural motifs, enabling E42 to specifically bind the AS1 allosteric site. The antiviral activity and cytotoxicity of E42 and E60 were evaluated using a SARS-CoV-2 trans-complementation cell culture system (containing mNG/Fluc) and the CCK-8 assay, respectively. The luciferase reporter assay revealed a consistent trend in antiviral activity among nirmatrelvir, E42, and E60, with E42 exhibiting moderate potency (EC50 = 13.79 ± 1.28 μM). Molecular dynamics simulations indicated that E42 inhibits 3CLpro activity by stabilizing its inactive conformation and disrupting protein allosteric equilibrium. Compared with conventional orthosteric inhibitors prone to drug resistance and poorly active, unsafe reported allosteric inhibitors, the optimized compounds in this study combine favorable potency and biosafety. This work provides novel lead structures and mechanistic insights for developing anti-COVID-19 3CLpro allosteric inhibitors.
