Molecular property prediction with deep learning often employs self-supervised learning techniques to learn common knowledge through masked atom prediction. However, the common knowledge gained by masked atom prediction dramatically differs from the graph-level optimization objective of downstream tasks, which results in suboptimal problems. Particularly for properties with limited data, the failure to consider domain knowledge results in a direct search in an immense common space, rendering it infeasible to identify the global optimum. To address this, we propose MPCD, which enhances pretraining transferability by aligning the optimization objectives between pretraining and fine-tuning with domain knowledge. MPCD also leverages multitask learning to improve data utilization and model robustness. Technically, MPCD employs a relation-aware self-attention mechanism to capture molecules’ local and global structures comprehensively. Extensive validation demonstrates that MPCD outperforms state-of-the-art methods for absorption, distribution, metabolism, excretion, and toxicity (ADMET) and physicochemical prediction across various data sizes.
2-(Methylthio)-N-(4-(naphthalen-2-yl)thiazol-2-yl)nicotinamide 1 was identified as an inhibitor against Chikungunya virus (CHIKV) with good antiviral activity [EC50 = 0.6 μM; EC90 = 0.93 μM and viral titer reduction (VTR) of 6.9 logs at 10 μM concentration] with no observed cytotoxicity (CC50 = 132 μM) in normal human dermal fibroblast (NHDF) cells. Structure–activity relationship (SAR) studies to further improve the potency, efficacy, and drug-like properties of 1 led to the discovery of a new potent inhibitor N-(4-(3-((4-cyanophenyl)amino)phenyl)thiazol-2-yl)-2-(methylthio)nicotinamide 26, which showed a VTR of 8.7 logs at 10 μM against CHIKV and an EC90 of 0.45 μM with considerably improved MLM stability (t1/2 = 74 min) as compared to 1. Mechanism of action studies show that 26 inhibits alphavirus replication by blocking subgenomic viral RNA translation and structural protein synthesis. The in vivo efficacy studies of compound 26 on CHIKV infection in mice are reported.
Recent advances in targeted protein degradation (TPD) have propelled it to the forefront of small molecular drug discovery. Among these, hydrophobic tagging (HyT) strategies have garnered significant interest. Carbon-based hydrophobic tags have been recognized as effective Hyts for degrading a variety of target proteins. In this study, we introduce a novel class of potential EGFR degraders for the first time, which combine Gefitinib with silicon-based hydrophobic tags (SiHyT). The most promising candidate, degrader 7, which links Gefitinib to a simple TBDPS silyl ether, has shown efficacy in degrading mutant EGFRs via the ubiquitin-proteosome system (UPS) both in vitro and in vivo. Notably, degrader 7 exhibits enhanced oral bioavailability owing to its superior metabolic stability compared to traditional carbon-based Hyts. Mechanistically, it was revealed that degrader 7 disrupts EGFR stability by dissociating the EGFR-HSP90 complex and recruiting E3 ligase, RNF149. More importantly, the potent and selective PD-L1 and BTK degraders were discovered successfully by utilizing the SiHyT strategy. The development of these innovative SiHyT compounds could broaden the repertoire of HyTs, enhancing the future design of TPD agents.
Microsomal prostaglandin E2 synthase 1 (mPGES-1) is a promising target for treating inflammatory diseases and pain. This study introduces a novel series of benzimidazoles, with the most potent analogs exhibiting IC50 values of 0.27–7.0 nM in a cell-free assay for prostaglandin (PG)E2 production. Compound 44 (AGU654) demonstrated remarkable selectivity for mPGES-1 (IC50 = 2.9 nM) over COX-1, COX-2, 5-LOX, and FLAP, along with excellent bioavailability. Metabololipidomics analysis with activated human monocyte-derived macrophages and human whole blood revealed that AGU654 selectively suppresses PGE2 production triggered by bacterial exotoxins while sparing other prostaglandins. Furthermore, in vivo studies showed that AGU654 significantly alleviated fever, inflammation, and inflammatory pain in preclinical guinea pig models, suggesting that it could be an effective strategy for managing inflammatory diseases. In conclusion, these benzimidazole derivatives warrant further exploration into new and alternative analogs, potentially uncovering novel compounds with a favorable pharmacological profile possessing significant anti-inflammatory and analgesic properties.
Herein, we describe and investigate biological activity of three octahedral ruthenium(II) complexes of the type [Ru(C∧N)(phen)2]+, RuL1–RuL3, containing a π-expansive cyclometalating substituted benzo[g]quinoxaline ligand (C∧N ligand) (phen = 1,10-phenanthroline). Compounds RuL1–RuL3 in cervical, melanoma, and colon human cancer cells exhibit high phototoxicity after irradiation with light (particularly blue), with the phototoxicity index reaching 100 for the complex RuL2 in most sensitive HCT116 cells. RuL2 accumulates in the cellular membranes. If irradiated, it induces lipid peroxidation, likely connected with photoinduced ROS generation. Oxidative damage to the fatty acids leads to the attenuation of the membranes, the activation of caspase 3, and the triggering of the apoptotic pathway, thus implementing membrane-localized photodynamic therapy. RuL2 is the first photoactive ruthenium-based complex capable of killing the hardly treatable colon cancer stem cells, a highly resilient subpopulation within a heterogeneous tumor mass, responsible for tumor recurrence and the metastatic progression of cancer.
The NLRP3 inflammasome has attracted much interest as a drug target; however, many of the first wave of inhibitors were derived from a single aryl sulfonylurea starting point. The physicochemical properties of this molecule and most derivatives are not amenable to high brain penetration, thus limiting their potential effectiveness against disease targets where this is required. The disclosure of a novel pyridazine phenol scaffold facilitated a second wave of research toward brain-penetrant molecules, which may enable the discovery of novel treatments for Alzheimer’s disease, Parkinson’s disease, multiple sclerosis and cardiometabolic diseases.