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Peptidomimetics are compounds whose essential elements (pharmacophore) mimic a natural peptide or protein in 3D space and which retain the ability to interact with the biological target and produce the same biological effect. Peptidomimetics are designed to circumvent some of the problems associated with a natural peptide: e.g. stability against proteolysis (duration of activity) and poor bioavailability. Certain other properties, such as receptor selectivity or potency, often can be substantially improved. The design and synthesis of peptidomimetics are most important because of the dominant position peptide and protein-protein interactions play in molecular recognition and signaling, especially in living systems. Hence mimics have great potential in drug discovery.

MCE Peptidomimetic Library contains 370 compounds including peptoid, α-helix mimetics, β-turn/sheets mimetics, etc. This library is an indispensable tool of structure-activity relationships in drug discovery.

Cell death plays a crucial role in the development of the body and the maintenance of internal balance to prevent the development of diseases. According to the regulation of the involved processes, cell death can be defined as programmed and non-programmed death. Programmed cell death (PCD) can be divided into lytic cell death and nonlytic cell death, mainly including apoptosis, necrotic apoptosis and Pyroptosis. Non-Programmed cell death (Non-PCD) generally refers to necrosis. In stark contrast to Accidental Cell Death (ACD), Regulatory Cell Death (RCD) relies on specialized molecular mechanisms. Cell death includes internal apoptosis, external apoptosis, necrotic apoptosis, ferroptosis, pyroptosis, lysosome-dependent cell death, etc.

MCE designs a unique collection of 3,640 cell death compounds, covering multiple targets, such as Apoptosis, Ferroptosis, Pyroptosis, Necroptosis, etc. It is a useful tool for screening cell death drugs.

Extracellular vesicles (EVs) are small membrane binding structures that are released from cells into the surrounding environment and play a crucial role in mediating and regulating intercellular communication related to physiological and pathological processes. EVs are lipid membrane vesicles composed of proteins, lipids, and nucleic acids. EVs can be divided into several types based on their source, such as extracellular vesicles, microcapsules, and apoptotic vesicles. The size range of exosomes is 30-150nm, which are endocrine in multi vesicular endosomes (MVEs); microvesicles (50-1000nm) are secreted directly through extracellular interactions, thereby releasing plasma membrane vesicles. In contrast, apoptotic bodies are usually larger, ranging in size from 1 to 5 μ m. This is generated during programmed cell death. EV plays a crucial role in transmitting information between cells and influencing the behavior and function of receptor cells.

MCE designs a unique collection of 643 small molecules related to extracellular vesicles (EVs). It is a good tool to be used for research on metabolize, cancer and other diseases.

G protein-coupled receptors (GPCRs) are membrane proteins in humans and one of the most important targets in drug discovery. Approximately 35% of launched drugs are targeted GPCRs, making them a crucial class of targets in drug discovery.

The orthosteric site of a GPCR is its endogenous ligand’s (such as neurotransmitters or hormones) binding site. This site plays a central role in signal transduction. Small molecules binding to this site typically contain a protonatable amino group, enabling the formation of salt bridges or hydrogen bonds with acidic residues in the binding pocket. In contrast, the allosteric site does not directly initiate signaling but modulates the signal intensity of the GPCR by altering or stabilizing the conformation of the orthosteric site. Small molecules binding to the allosteric site often contain multiple aromatic rings to occupy hydrophobic pockets and achieve their functional effects.

MCE has collected over 7,115 reported bioactive molecules targeting GPCRs, covering Class A, B, and C GPCRs. These small molecules were subjected to AI representation to extract 2D and 3D features. Subsequently, we do screening by AI score based on similarity to identify molecules in diversity library highly similar to the reported bioactive molecules in both 2D and 3D, with a threshold greater than 0.7. Further screening based on cLogP was applied to select molecules with good lipophilicity, which facilitates the binding of small molecules to GPCRs. This diversity library can be widely applied to the discovery of compounds targeting GPCR proteins.

DEL technology enables the simultaneous screening of millions or billions of compounds in a single tube by covalently linking each small molecule with a unique DNA sequence. Traditional DEL screening primarily focuses on identifying non-covalent binding molecules, where interactions with the target are reversible. In contrast, DNA‑encoded covalent library is an ultra‑high‑throughput screening library developed on the basis of conventional DNA‑encoded library technology. It incorporates controllable electrophilic covalent warheads capable of forming irreversible covalent bonds with amino acid residues at the active sites of target proteins, including Cys, Lys, Ser, Tyr, and others. This covalent binding enhances binding affinity, prolongs residence time at the target site, and has the potential to overcome challenges associated with traditional non-covalent inhibitors, such as drug resistance or off-target effects.

Each compound in the library contains both a binding domain and an electrophilic warhead. It first recognizes and binds to the target through non covalent interactions, and then forms a stable covalent bond with key amino acid residues to achieve irreversible inhibition. This library is specifically designed for the discovery of potent, long lasting, and highly selective covalent inhibitors, particularly for undruggable targets such as kinases, GPCRs, proteases, and mutant oncoproteins. Each molecule is uniquely labeled with a DNA barcode for molecular identification and sequencing decoding.

This library is an advanced and highly diverse collection, consists of 35 independent sub-libraries with a total scaleof 14 million compounds, It incorporates over 14 experimentally validated covalent warheads capable of targeting cysteine, lysine, arginine, aspartic acid and glutamic acid. This library is constructed with diverse drug like core scaffolds and integrated controllable covalent warheads, it features structural diversity, reaction spec

In contrast to the high conservation of conventional orthosteric sites, allosteric sites possess structural characteristics of low conservation, high hydrophobicity, weak polarity, confined spatial geometry, and dynamic cryptic properties. There is a significant difference between their core structures and orthosteric pockets — allosteric pockets are mostly dynamic grooves formed by protein conformational changes, subunit interface clefts, or shallow depressions, rather than the rigid "keyhole" structure of orthosteric sites. With looser spatial constraints, allosteric sites have the advantages of high selectivity and low off-target risk, and have become an important direction in new drug discovery.

Based on the dynamic, hydrophobic, and narrow-long spatial characteristics of allosteric pockets, MCE has performed targeted modification and screening of fragments. The screening criteria strictly conform to the requirements of allosteric binding: molecular weight is controlled at 120–280 Da (to meet the core needs of small molecules in fragment libraries and high derivatization), hydrogen bond donors (HBD ≤ 2), hydrogen bond acceptors (HBA ≤ 3), polar surface area (PSA = 30–80 Ų), rotatable bonds (≤ 2), moderate hydrophobicity (cLogP = 1–3.5), no strongly ionizable groups, and both appropriate rigidity and conformational flexibility to adapt to the dynamic changes of the pocket. Meanwhile, combined with the results of principal moment of inertia (PMI) analysis, fragments with high 3D diversity were obtained. Such fragments have good shape complementarity with allosteric pockets, ensuring that the fragments can smoothly enter the allosteric pockets and form stable binding, while providing room for subsequent optimization and derivation.

This library contains 1,800 structurally diverse fragment molecules with excellent drug-like properties, suitable for allosteric drug development and the design and optimization of allosteric sites. It combines the

Owing to the high conservation of orthosteric sites, conventional orthosteric drugs frequently suffer from poor subtype selectivity, off-target toxicity, and drug resistance, severely restricting their clinical application. In contrast, allosteric sites feature low conservation, high hydrophobicity, weak polarity, confined spatial geometry, and dynamic cryptic properties. These characteristics endow allosteric modulators with distinct advantages including high selectivity, functional tunability, and improved safety, making allosteric therapy a key direction in modern drug discovery.

MCE has curated nearly 1,000 structurally disclosed clinical-stage allosteric modulators. By analyzing allosteric protein–ligand complex structures from the PDB database, we extracted core pharmacophores and privileged scaffolds. Adopting a rational design strategy of “scaffold derivation + allosteric physicochemical filtering”, we performed secondary screening on the derived compounds strictly following the optimal physicochemical principles for allosteric binding based on universal allosteric pocket properties: molecular weight 300–500 Da, HBD ≤ 3, HBA = 3–8, PSA = 70–120 Ų, rotatable bonds ≤ 6, highly rigid scaffolds, cLogP = 1.0–3.8, and no strongly ionizable groups. The selected compounds exhibit high rigidity and shape complementarity, making them well-suited for targeting shallow, dynamic, and hydrophobic-dominated allosteric pockets.

This allosteric modulator library contains 4,315 structurally diverse, lead-like compounds dedicated to allosteric drug development, allosteric site targeting, and allosteric modulator screening. It is suitable for kinases, GPCRs, and other important drug targets. All compounds are analogs of clinical-stage allosteric modulators with a similarity score > 0.6, combining excellent druggability and allosteric binding potential. It provides a highly efficient tool for early-stage allosteric drug discovery.

MCE Modified Safranin O–Fast Green Cartilage Staining Kit through an optimized staining system, cartilage matrix and bone tissue in histological sections can be clearly distinguished. This method provides high staining contrast, good sensitivity, simple operation, and good reproducibility, and is widely used for cartilage morphology observation, studies of cartilage injury and degeneration, osteochondral tissue development research, and related histological analyses.

MCE Masson Staining Kit can simultaneously stain various tissue components, such as cell nuclei, collagen fibers, and muscle fibers. It features low toxicity, environmental friendliness, simple operation, and stable performance. The staining results show clear coloration and high contrast. The stained sections can be stored for long periods with minimal fading, facilitating long-term preservation and image analysis. This kit is widely used in studies of connective tissue, muscle tissue, and collagen fibers, and is suitable for histological observation and related pathological analyses.

MCE Modified Masson Staining Kit employs Celestine Blue hematoxylin for light nuclear staining, offering shorter differentiation time compared to conventional methods. It features low toxicity, environmental friendliness, simple operation, and stable performance. The staining results show clear coloration and high contrast. The stained sections can be stored for long periods with minimal fading, facilitating long-term preservation and image analysis. This kit is widely used in studies of connective tissue, muscle tissue, and collagen fibers, and is suitable for histological observation and related pathological analyses.