translational diffusion coefficient

Lysine is the second most common target residue used in the design of TCIs and related covalent ligands. Its appeal lies in its abundance in human proteins, which is approximately three times higher than that of cysteine (5.8% vs. 1.9%). This significantly increases the number of proteins suitable for covalent targeting, especially given that many human proteins lack ligandable cysteine residues. Moreover, it has been suggested that functional lysines have a lower probability of being replaced by mutation, as they often play a crucial role in catalysis by acting as bases or nucleophiles. Additionally, lysines are essential for maintaining the structural integrity of proteins and for regulating post-translational modifications (PTMs). Consequently, targeting lysine has garnered significant interest in recent years.

Through careful selection, we constructed a structural filter containing over 110 electrophilic groups. By analyzing the electrophilic fragments selected by the structural filter, we removed any molecules with trivial or undesirable structural features. Ultimately, we obtained 445 fragment molecules which can target lysine residue and can be used for fragment-based covalent drug discovery.

Protein phosphorylation is a key post-translational modification underlying the regulation of many cellular processes. Phosphatases and kinases contribute to the regulation of protein phosphorylation homeostasis in the cell. This reversible regulation of protein phosphorylation is critical for the proper control of a wide range of cellular activities, including cell cycle, proliferation and differentiation, metabolism, cell-cell interactions, etc.

Protein phosphatases have evolved in separate families that are structurally and mechanistically distinct. Based on substrate specificity and functional diversity, protein phosphatases are classified into two superfamilies: Protein serine/threonine phosphatases and Protein tyrosine phosphatases. Ser/Thr phosphatases are metalloenzymes belonging to two major gene families termed PPP (phosphoprotein phosphatase) and PPM (metal-dependent protein phosphatases), whereas protein tyrosine phosphatases (PTPs) belong to distinct classes of enzymes that utilize a phospho-cysteine enzyme intermediate as a part of their catalytic action.

MCE supplies a unique collection of 185 phosphatase inhibitors that mainly targeting protein tyrosine phosphatases (PTPs) and serine/threonine-specific protein phosphatases. MCE Phosphatase Inhibitor Library is a useful tool for phosphatase drug discovery and related research.

Research has shown that drugs targeting aging pathways demonstrate promising potential in models of age-related diseases such as Alzheimer's disease, cardiovascular diseases, metabolic syndrome, osteoarthritis, and various malignancies. This suggests that intervening in the biological processes of aging may enable synergistic prevention and treatment of multiple chronic diseases. Against the backdrop of the gradual elucidation of core aging mechanisms-including cellular senescence, telomere attrition, epigenetic dysregulation, and chronic inflammation anti-aging research has shifted from traditional phenotypic interventions toward targeting key pathways that regulate biological age.

The MCE Anti-Aging Compound Library Mini is precisely built upon this cutting-edge concept. It focuses on aging-related targets validated through genetic or functional studies, comprising 381 compounds designed to provide systematic research tools for aging biology and intervention strategy development. The library covers core mechanisms such as mTOR, SIRT, energy metabolism, clearance of senescent cells, optimization of mitochondrial function, and telomere maintenance. For each target, 1-5 compounds with clear activity and strong representativeness have been carefully selected, spanning the entire translational spectrum from preclinical tool molecules to clinically investigational drugs.

Ionizable lipids are a class of specialized, functional lipid molecules with pH-sensitive charge characteristics. They are primarily divided into two major categories: ionizable cationic lipids and ionizable anionic lipids, though the term typically specifies ionizable cationic lipids within the biomedical field. Structurally, these lipids consist of an ionizable hydrophilic headgroup, a biodegradable linker, and hydrophobic tails. Their primary application is serving as the key delivery vehicle in lipid nanoparticles (LNPs) to encapsulate negatively charged nucleic acid macromolecules, such as mRNA vaccines, siRNA therapeutics, and CRISPR gene-editing components. In a physiological, neutral environment, they remain electrically neutral to minimize systemic toxicity and prolong circulation time. Upon entering the acidic microenvironment of cellular endosomes, however, they undergo protonation to become positively charged, thereby inducing membrane fusion and enabling the highly efficient intracellular release of the nucleic acid cargo. Consequently, they serve as the technological cornerstone for bringing nucleic acid therapies into clinical application.

To accelerate the translational process of cutting-edge nucleic acid drugs, MCE has meticulously constructed an ionizable lipid compound library containing 93 high-performance molecules, aiming to provide researchers and pharmaceutical professionals with a high-throughput, multi-dimensional lipid screening platform.

Fragment-based drug discovery (FBDD) is well suited for discovering both drug leads and chemical probes of protein function. 3-dimensionality (3D) diversity is pivotal because the molecular shape is one of the most important factors in molecular recognition by a biomolecule. There is a developing appreciation that 3D fragments could offer opportunities that are not provided by 2D fragments.

MCE 3D Diverse Fragment Library consists of 5,400 non-flat fragment-like molecules (average Fsp3 value 0.58). More than 4,700 fragment compounds contain at least one chiral center in the structure. The key concepts that underlie the library design were 3D shape, structural diversity, reactive functionality and fragment-like. This 3D Diverse Fragment Library brings higher fragment hit optimization and increases the likelihood to find innovative hits in FBDD.

Protein lactylation, an emerging post-translational modification identified in recent years, plays a critical role in linking cellular metabolic reprogramming, epigenetic regulation, and signaling networks. Based on a systematic framework encompassing lactate metabolism, lactylation, and downstream signaling pathways, this compound library comprehensively targets multiple regulatory layers, including histone modification enzymes (such as p300 and HDACs), key glycolytic enzymes (such as PKM2, LDHA, and GAPDH), transcriptional regulators (such as STAT3, HMGB1, and p53), as well as central signaling pathway nodes including HIF-1α, NF-κB, and PI3K-AKT-mTOR. This integrated design enables a comprehensive representation of the regulatory roles of lactylation across the “metabolism–epigenetics–signaling” axis.

MCE has assembled a collection of 6,182 known bioactive compounds and potential functional molecules, making this library suitable for a wide range of applications, including high-throughput drug screening, inhibitor identification, and mechanistic studies. It can be used to systematically evaluate the functional roles of lactylation in biological processes such as tumor metabolism, immune regulation, and inflammatory responses, and to efficiently identify small-molecule candidates with regulatory potential, thereby facilitating the development of innovative therapeutics targeting the interplay between metabolism and epigenetic regulation.