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Antimicrobial Peptides (AMPs), also known as antimicrobial peptides or antibiotic peptides, are a class of polypeptides encoded by specific genes in various biological cells and induced by external stimuli. They exhibit broad-spectrum bioactivity against bacteria, fungi, viruses, protozoa, and even tumor cells. AMPs serve as crucial effector molecules in the host's innate immune system.Due to their wide antimicrobial spectrum, low toxicity to normal cells of higher animals, high safety profile, low tendency to induce resistance, and additional benefits such as immune enhancement and antioxidant effects, antimicrobial peptides hold significant promise in new drug development.

MCE offers 57 types of antimicrobial peptides, which can be applied in high-throughput screening for research in anti-infection therapies, immunotherapy, anticancer drug development, and agricultural disease control.

Depression is a serious global affective disorder and one of the most common neurological diseases whose clinical manifestations are low mood, loss of interest, anhedonia, loss of energy, and fatigue, people with major depressive disorder (MDD) can even have suicidal thoughts and behaviors.

Currently available antidepressants have significant limitations, including a long time lag for a therapeutic response (weeks to months) and low response rates. This is particularly problematic for a disease with a high suicide rate. Therefore, the development of new antidepressant drugs is particularly urgent.

MCE offers a unique collection of 2,857 compounds with antidepressant activities or targeting the unique targets of depression. MCE Antidepressant Compound Library is a useful tool for exploring the mechanism of depression and discovering new drugs for depression.

Most of the drugs that are available in the marketplace are administered via the oral route, which is a convenient and cost effective route of administration. Thus, oral bioavailability is one of the key considerations in drug design and development. A high oral bioavailability reduces the amount of an administered drug necessary to achieve a desired pharmacological effect and therefore could reduce the risk of side-effects and toxicity. A poor oral bioavailability can result in low efficacy and higher inter-individual variability and therefore can lead to unpredictable response to a drug. Low oral bioavailability in clinical trials is a major reason for drug candidates failing to reach the market.

MCE offers a unique collection of 5,259 compounds with confirmed high oral bioavailability. MCE Orally Active Compound Library is a useful tool for discovering new drugs with oral bioavailability.

MCE Targeted Diversity Library contains 2,300 compounds, covering more than 1000 targets and isoforms, such as GPCRs, Ion channel, variety of kinases, etc. 1-3 compounds with high potency and selectivity were carefully selected for each target and isoform. The bioactivity information of each compound has been clearly reported in the literatures. This library is a concise collection of small molecule compounds with comprehensive target coverage, which can be used for phenotypic screening at low cost.

Plant hormones are natural signaling molecules synthesized by plants themselves, serving as crucial chemical messengers that exert physiological effects on plants at extremely low concentrations. They coordinate cellular growth, division, differentiation, and organ formation, helping plants adapt to environmental changes. Major categories include abscisic acid, auxins, gibberellins, cytokinins, ethylene, and brassinosteroids, among others.

MCE has included 46 plant hormones, which can be used for identification in plant metabolomics and related botanical research.

Drug repurposing (also called drug repositioning, reprofiling, or re‑tasking) offers various advantages over developing an entirely new drug for a given indication, for example, lower risk of failure, less investment, and shorter development timelines. But drug repositioning projects are also subject to several risks, including regulatory and intellectual property issues. So the off-patent drugs are optimal for repositioning because of their immediate availability for clinical studies, with high feasibility and relatively low risk.

MCE carefully prepared a unique collection of 2,897 off-patent drugs, which is a good choice for drug repurposing.

Fragment-based drug development (FBDD) is a strategy for drug discovery that can be applied both academically and commercially to enhance the identification of some non-drug targets. Fragment-based drug development has identified low molecular weight molecules (<300 Da) capable of binding to related macromolecules. These fragments can cover a wide chemical space and are easy to optimize later. Currently, several fragment-based drugs have entered clinical trials, of which two drugs, Vemurafenib and Venetoclax, have been approved for marketing.

Based on Tanimoto coefficient, MCE uses similarity algorithm to carefully select 2,258 high-structurally diverse 'RO3' compliant fragment molecules from large-scale fragment molecules, which can be applied to fragment based drug development.

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

Targeted cancer therapies are drugs or other substances that block the growth and spread of cancer by interfering with specific molecular targets that are involved in the growth, progression, and spread of cancer.

There are several different types of targeted therapy. The most common types are small-molecule drugs and monoclonal antibodies. Small-molecule drugs are small enough to enter cells easily, so they are used for targets that are inside cells, while monoclonal antibodies are usually used for targets that are located outside the cells. Because of high specificity, low side effect and potent anticancer activity, targeted therapy has become the mainstream of new anti-tumor drugs. Various targeted therapies have been approved by FDA and used in the treatment of diseases.

MCE carefully collects a unique of 108 targeted therapy drugs used in cancer treatment. MCE Targeted therapy drug library is a useful tool for the research of targeted therapy.

Hematopathy, also known as hematopoietic system diseases, are a class of diseases that hematopoietic system has abnormal changes. Common hematopathy include: aplastic anemia, myeloproliferative diseases, thalassemia, leukemia, lymphoma, myeloma and hemophilia, etc. In recent years, treatments for hematopathy have been developed. In particular, the treatment of malignant hematopathy developed from chemotherapy, radiotherapy, bone marrow development to immunotherapy, induced differentiation therapy, cell therapy, gene therapy and hematopoietic stem cell transplantation. Although these therapies have greatly improved the survival rate of patients, there are still problems such as low cure rate and easy recurrence in the treatment of hematopathy. Therefore, it is of great significance to actively search for new hematopathy therapeutic drugs.

MCE designs a unique collection of 4,131 anti-hematopathy small molecules, which is an effective tool for development and research of anti-hematopathy compounds.

Cyclic peptides are polypeptide chains taking cyclic ring structure, which exhibit diverse biological activities, such as antibacterial activity, immunosuppressive activity and anti-tumor activity. Cyclic peptides, with the features of good binding affinity, target selectivity and low toxicity, show great success as therapeutics. Multiple cyclic peptides are currently in clinical use, for examples, gramicidin and tyrocidine with bactericidal activity, cyclosporin A with immunosuppressive activity, and vancomycin with antibacterial activity. Furthermore, cyclic peptides usually have the sufficient size and a balanced conformational flexibility/rigidity for binding to flat protein-protein interaction (PPI) interfaces, which have potential to develop PPI drugs.

MCE offers a unique collection of 97 cyclic peptides, all of which have good bioactivities. MCE Cyclic Peptide Library is a powerful tool for drug discovery and PPI inhibitor screening.

At the forefront of innovative drug discovery, every medicinal chemist faces the challenge of rapidly identifying high-quality hit compounds from vast repositories of chemical resources.

The MCE Natural Product Diversity Scaffold Library is the result of a streamlined optimization process built upon our existing natural product collection. Adhering to the rigorous selection principle of "retaining only one representative compound per BMS scaffold", we have concentrated the diversity of thousands of compounds into a high-value, low-redundancy core set containing 2,272 compounds. All compounds are derived from natural sources, inheriting their inherent advantages of structural complexity and drug-likeness. By eliminating redundancy, the library size is significantly reduced without any compromise to chemical diversity. This approach effectively lowers the cost and time required for primary screening while simplifying downstream data analysis and structure-activity relationship (SAR) studies.

Chinese Baijiu is one of the oldest alcoholic beverages in the world, with a history of over 2,000 years. It can be classified into 12 aroma types based on its fragrance and flavor characteristics. The specific flavor profile of Baijiu is determined by the composition and concentration of certain compounds. These trace compounds, present in low concentrations yet rich in esters, alcohols, acids, lactones, aldehydes, ketones, acetals, alkenes, and others, significantly influence the flavor of Baijiu. Additionally, some active components in Baijiu possess antioxidant properties, and moderate consumption may help reduce the risk of cardiovascular diseases, dementia, and insulin resistance. Therefore, studying the chemical composition of Baijiu is crucial for promoting its fermentation process and enhancing its flavor and quality.

MCE has compiled included 662 Chinese Baijiu components, which can be used for drug development, Baijiu fermentation, and research related to Baijiu flavor and aroma.

New drug development is a time-consuming and high-cost process. Drug repurposing (also called drug repositioning, reprofiling or re‑tasking) offers various advantages over developing an entirely new drug for a given indication, such as lower risk and less investment. Clinical drugs have confirmed bioactivities, clear mechanisms and high safety that are suitable for drug repurposing.

MCE owns a unique collection of 3,217 clinical compounds that refer to various research areas including anti-cancer, anti-infection, anti-inflammation, nervous disease. Those compounds are of detailed information on clinical development status, research area, targets, etc. Clinical Compound Library Plus, with powerful screening capability, further complements Clinical Compound Library (HY-L026) by adding some compounds with low solubility or solution stability (Part B) to this library. All those supplementary are supplied in powder form.

Radiotherapy is a common treatment for various cancers, and more than 50% of cancer patients require radiotherapy during the disease treatment. With advances in radiation technology and a better understanding of tumor biology, the efficacy of radiation therapy has gradually improved, and more and more patients have benefited from it. However, even with the use of advanced radiotherapy techniques, there are still many malignant tumor cells with low sensitivity to radiation, leading to the radiation effect is not ideal. To solve this problem, radiosensitizers have received more and more attention. Radiosensitizer is a kind of drug that can enhance the radiosensitivity of tumor cells and improve the effect of radiotherapy. Radiation sensitizers act in a variety of ways, such as killing hypoxic cells, enhancing DNA damage, inhibiting DNA damage repair, and blocking cell cycle progression, making tumor cells more susceptible to radiation damage and death than surrounding normal cells.

MCE designs a unique collection of 41 compounds with definite reported radiosensitization. It can be used for drug combination research in anti-cancer treatment.

New drug development is a time-consuming and high-cost process. Drug repurposing (also called drug repositioning, reprofiling or re‑tasking) offers various advantages over developing an entirely new drug for a given indication. First, the risk of failure is lower. Second, the time frame for drug development can be reduced. Third, less investment is needed. Approved drugs have identified bioactivities, good pharmacokinetic characteristics and safety which are suitable for drug repurposing.

MCE owns a unique collection of 3,640 approved compounds which have been completed extensive preclinical and clinical studies and have well-characterized bioactivities, safety and bioavailability properties. MCE FDA-Approved Drug Library Plus, with more powerful screening capability, further complements FDA-Approved Drug Library (HY-L022) by adding some compounds with low solubility or solution stability (Part B) to this library. All those supplementary are supplied in powder form.

A diverse compound library with favorable ADMET properties (Absorption, Distribution, Metabolism, Excretion, and Toxicity) is crucial in drug discovery. Early evaluation of ADMET properties allows for the exclusion of molecules with unfavorable profiles at the initial stages, thereby reducing the risk of late-stage development failures, lowering R&D costs, and accelerating optimization of lead compounds. Based on predictions from ADMET-related AI algorithms, the compounds in this library are predicted to exhibit favorable oral bioavailability (F > 30%), reasonable plasma protein binding (PPB < 98%), minimized CYP3A4 inhibition potential (inhibition probability < 50%, CYP3A4 is the most critical drug-metabolizing enzyme in the cytochrome P450 family) , low toxicity profiles, with 140 potentially toxic substructures pre-identified and excluded via substructure searching to eliminate compounds containing hazardous fragments. The diversity library enables broad applicability in high-throughput screening (HTS) and high-content screening (HCS).

Gastric Cancer (GC) is one of the most common malignant tumors in the world, ranking fourth in mortality rate globally. Because the early symptoms of stomach neoplasm are usually not obvious, are diagnosed with gastric cancer at terminal stage, and the relative survival rate within 5 years is very low. With the further understanding of the molecular characteristics of stomach neoplasm, many therapeutic targets for gastric cancer have been identified, and molecular targeted therapies such as CTLA-4, HER2 and immune checkpoint inhibitors have made rapid progress. Although survival rates for patients with gastric neoplasm have improved over the past few decades, the prognosis is still worrying. Therefore, there is an urgent need for new drugs to treat gastric cancer.

MCE designs a unique collection of 1,103 small molecules with definite or potential anti-gastric cancer activity, which is an important tool for studying the pathological mechanism of stomach neoplasm and developing drugs for stomach neoplasm.

Cytokines are a kind of low molecular soluble proteins synthesized and secreted by immunogen, mitogen or other factors. They have functions of regulating innate and adaptive immune responses, promoting hematopoiesis, stimulating cell activation, proliferation and differentiation. The process of releasing a large number of cytokines is also called “Cytokine storm”, which can cause damage to many tissues and organs in the body. Cytokine is involved in the pathogenesis of many human diseases, including cancer, diabetes, chronic inflammatory diseases and so on. Cytokine inhibitors are a class of essential compounds that act by directly inhibiting the synthesis and release of cytokine or blocking the binding of cytokine to their receptors. Cytokine inhibitors are important compounds for the study of tumor and autoimmune diseases.

MCE designs a unique collection of 1,320 cytokine inhibitors, mainly targeting the receptor interleukin (IL), colony-stimulating factor (CSF), interferon (IFN), tumor necrosis factor (TNF), growth factor (GF) and chemokine, which is an effective tool for development and research of anti-cancer, anti-chronic inflammatory diseases and anti-autoimmune diseases compounds.

New drug development is a time-consuming and high-cost process. Drug repurposing (also called drug repositioning, reprofiling or re‑tasking) offers various advantages over developing an entirely new drug for a given indication. First, the risk of failure is lower. Second, the time frame for drug development can be reduced. Third, less investment is needed. Approved and clinical drugs, especially after phase I drugs, have identified bioactivities, good pharmacokinetic characteristics and safety, which are suitable for drug repurposing.

MCE Drug Repurposing Compound Library plus contains 6,065 approved and passed phase I clinical drugs, which have been completed extensive preclinical and clinical studies and have well-characterized bioactivities, safety and bioavailability properties.

MCE Drug Repurposing Compound Library plus, with more powerful screening capability, further complement MCE Drug Repurposing Compound Library (HY-L035) by adding some compounds with low solubility or stability (Part B) to this library. All those supplementary compounds are supplied in powder form.

Natural products are small molecules produced naturally by any organism including primary and secondary metabolites. Natural sources may lead to basic research on potential bioactive components for commercial development as lead compounds in drug discovery.

Nature has been a source of medicinal agents for thousands of years, and an impressive number of modern drugs have been isolated from natural sources, many based on their use in traditional medicine. With the development of new molecular targets, there is an increasing demand for novel molecular diversity for screening. Natural products will play a crucial role in meeting this demand through the continued investigation of world’s bio-diversity, much of which remains unexplored.

MCE provides a unique collection of 6,174 natural compounds that contains Saccharides and Glycosides, Phenylpropanoids, Quinones, Flavonoids, Terpenoids and Glycosides, Steroids, Alkaloid, Phenols, Acids and Aldehydes. Natural Product Library Plus, with more powerful screening capability, further complements Natural Product Library (HY-L021) by adding some compounds with low solubility or solution stability (Part B) to this library. All those supplementary are supplied in powder form.

Pancreatic cancer is a devastating disease with a low overall survival rate. Chemotherapy is the most common treatment for patients presenting with advanced pancreatic cancer. More recently, the era of targeted therapies has generated a lot of interest in discovering better approaches for patients with pancreatic cancer. Commonly mutated genes in pancreatic cancer include K-ras (in 74-100% of cases), p16INK4a (up to 98%), p53 (43 to 76%), DPC4 (about 50%), HER-2/neu (in about 65%) and FHIT (found in 70% of cases). Other genes involved are notch1, Akt-2, BRCA2 and COX-2. These proteins are important targets of target therapies for pancreatic cancer.

MCE offers a unique collection of 4,096 compounds with identified and potential anti- pancreatic cancer activity. These compounds target K-Ras, p53, HER2, Notch, AKT, etc. MCE anti-pancreatic cancer compound library is a useful tool for anti-pancreatic cancer drugs screening and other related research.

In this era of rapid advancement in gene-editing technology, the CRISPR-Cas system, with its powerful programmability, is leading a transformation in life sciences research. It enables efficient and precise targeted modification of an organism's genome, providing a robust tool for studying gene function, treating genetic diseases, and improving crop varieties. However, bottlenecks such as insufficient editing efficiency, low homologous directed repair efficiency, and potential off-target risks remain major challenges in achieving precise genetic modifications and developing gene therapies.

To overcome these limitations, the MCE High-Efficiency Gene Editing Compound Library systematically includes 724 small molecules that are known or have the potential to enhance gene-editing efficiency. These compounds work by targeting and modulating the DNA damage repair network, mechanistically inhibiting non-homologous end joining, promoting homologous directed repair, or regulating chromatin states and cellular responses, thereby significantly optimizing editing outcomes. This library is suitable for developing "CRISPR-small molecule" combination therapy strategies, improving gene-editing efficiency, and providing a powerful tool for in-depth research into the mechanisms of DNA damage repair in gene editing.

Liposomes are spherical or multilayered spherical vesicles formed by the self-assembly of diacyl chain phospholipids (lipid bilayers) in aqueous solutions, which can be made from natural or synthetic phospholipids and exhibit good biocompatibility and low toxicity. They can serve as delivery carriers for various bioactive substances (such as drugs, proteins, nucleic acids, etc.) and are widely used in biomedical and chemical research. The main advantages of liposomes include 1) Protective effect: Their bilayer structure can protect encapsulated molecules from enzymatic degradation, oxidation, and other influences, extending stability and activity; 2) Active targeting: Surface modifications enable active targeting, enhancing the concentration of drugs or molecules in specific tissues or cells; 3) Customizability: The composition and structure of liposomes can be adjusted according to needs, such as altering phospholipid types or adding targeting ligands. These properties make liposomes highly valuable in developing novel drug delivery systems, serving as nucleic acid carriers for gene transfection, studying cellular uptake mechanisms and drug release kinetics, as well as developing functional food additives to improve the bioavailability of nutritional components.

MCE contains 192 liposome compounds, which is a good tool for lipidomic-related studies.

Cyclic peptide library have advantages such as high affinity, high selectivity, and suitability for targeting protein–protein interactions. Through DEL synthesis technology, the library size can achieve hundreds of millions. DEL cyclic peptide library have advantages like low cost andhigh screeing efficiency, making them valuable for discovering lead compounds against challenging drug targets.

This cyclic peptide library is constructed with unnatural amino acids as building block, synthesized through DNA-compatible chemical reactions. Each cyclic peptide consist of six amino acids and constrained conformations such as side-chain cross-linking, disulfide bonds, and macrocyclization. These cyclic peptides exhibit significantly improved stability and druggability compared with linear peptides, filling the gap between small molecules and macromolecular biologics. Each cyclic peptide is uniquely conjugated to a DNA barcode sequence for molecular identification and sequencing decoding.

MCE’s cyclic peptide library has8 independent sub-libraries, with a total molecular diversity of 1.2 billion. It is constructed via multi-round combinatorial assembly of building blocks and diverse cyclization strategies, facilitating the discovery of cyclic peptide leads for undruggable targets.

With the aging population and increasing competitive pressures, neurodegenerative diseases of the central nervous system (CNS) have become a serious medical challenge in modern society, including Parkinson's disease, Alzheimer's disease, brain tumors, and multiple sclerosis. However, the success rate of CNS drug development remains remarkably low, primarily due to the blood-brain barrier (BBB). The blood-brain barrier (BBB) is a semipermeable barrier structure that surrounds the microvasculature of the CNS. In capillaries, the wedged endothelial cells are tightly packed and wedge-shaped, lining the interior of the vessels to form extensive tight junctions. Along with a range of receptors, transporters, efflux pumps, and other cellular components, this barrier regulates the entry and exit of molecules between the bloodstream and the brain. The intact BBB blocks the passage of most blood-borne substances into the brain, preventing nearly 100% of large-molecule drugs and over 98% of small-molecule drugs from entering. Compared to non-CNS drugs, physicochemical properties such as hydrogen bonds, lipophilicity, and molecular weight significantly influence a compound's ability to cross the BBB. Using artificial intelligence (AI) algorithms to predict BBB permeability, a predicted value greater than 0.75 indicates that the compound has strong potential to cross the BBB, providing a promising starting point for CNS drug discovery.

Bioactive compounds are a general term for a class of substances that can cause certain biological effects in the body, which are the main source of small molecule drugs. These compounds generally penetrate cell membranes, act on specific target proteins in cells, regulate intracellular signaling pathways, and cause some changes in cell phenotype.

MCE owns a unique collection of 32,758 compounds with confirmed biological activities and clear targets. These compounds include natural products, innovative compounds, approved compounds, and clinical compounds. This library is a useful tool for signal pathway research, drug discovery and drug repurposing, etc.

Bioactive Compound Library Plus, with more powerful screening capability, further complements Bioactive Compound Library (HY-L001) by adding some compounds with low solubility or solution stability (Part B) and some novel, rare or exclusive compounds (Part C) to this library. Overall, bioactive compound library plus (HY-L001P) includes tree parts: Part A, Part B and Part C. Compounds in Part A are equal to the products in HY-L001, which can be supplied in solution or solid form. Compounds in Part B and C are only supplied in solid form.

Macrocyclic compounds (≥12-atom cyclic small molecules/peptides) have unique physicochemical properties. They form preorganized conformations with high binding affinity/selectivity, target traditional small-molecule-inaccessible proteins, and bridge small-molecule drugs and biological agents. As key protein phosphorylation enzymes, kinases are linked to tumors, COPD, etc., and are critical therapeutic targets. Traditional small-molecule kinase inhibitors lack selectivity, causing off-target toxicity, low bioavailability, and acquired resistance. Macrocycles’ semi-rigid structure restricts conformations, boosts binding selectivity, optimizes pharmacokinetics, and makes macrocyclization a core kinase inhibitor optimization strategy.

Thousands of bioactive macrocycles were curated from ChEMBL. Via Transformer, macrocyclization was converted into a chemical language translation task, enabling end-to-end macrocycle generation from linear precursors with simplified inputs. Macformer achieves efficient, automated linear molecule macrocyclization via deep learning; generated macrocycles have diversity, novelty, biocompatibility, and cover broader chemical space.

MCE collected thousands of marketed/clinical kinase inhibitors, using their fragments for macrocyclization to generate derivatives. After evaluating synthetic accessibility and physicochemical properties, a million-scale virtual macrocyclic library was built for kinase-related virtual and AI-driven screening.

Withdrawal or delisting drugs refer to drugs that are recalled or discontinued from the market due to low efficiency, serious side effects, financial and regulatory problems and other reasons. Once the drug is withdrawn from the market, it will cause heavy losses to the original research company that invested a lot of time, finance and other costs to develop the drug.

Adverse drug reaction (ADR) is the main reason for drug withdrawal from the market. ADR refers to the unexpected effects caused by the reasons such as the target-directed interaction during the treatment. However, studying the mechanism of these ADRs may just be a breakthrough in finding new indications. For example, thalidomide, the protagonist of the drug damage event that caused numerous "seal babies" deformed infants, was found to be due to the degradation of a transcription factor - SALL4 after delisting, which made thalidomide have a new clinical application. In 1998, it was approved by FDA for the treatment of leprosy nodular erythema, and in 2006, it was approved for the treatment of multiple myeloma. ADR study of delisted drugs can not only avoid the loss of drug development in advance but also bring hope to new indications.

MCE has sorted out 231 drug compounds withdrawn from the market through FDA, EMA and other authoritative platforms. Each compound has withdrawal records in at least one country/market. It is a useful tool for conducting research on drug side effects or drug toxicity mechanisms and discovering new indications of drugs.

Macrocyclic compounds (≥12-atom cyclic small molecules/peptides) have unique physicochemical properties. They form preorganized conformations with high binding affinity/selectivity, target traditional small-molecule-inaccessible proteins, and bridge small-molecule drugs and biological agents. As key protein phosphorylation enzymes, kinases are linked to tumors, COPD, etc., and are critical therapeutic targets. Traditional small-molecule kinase inhibitors lack selectivity, causing off-target toxicity, low bioavailability, and acquired resistance. Macrocycles’ semi-rigid structure restricts conformations, boosts binding selectivity, optimizes pharmacokinetics, and makes macrocyclization a core kinase inhibitor optimization strategy.

Thousands of bioactive macrocycles were curated from ChEMBL. Via Transformer, macrocyclization was converted into a chemical language translation task, enabling end-to-end macrocycle generation from linear precursors with simplified inputs. Macformer achieves efficient, automated linear molecule macrocyclization via deep learning; generated macrocycles have diversity, novelty, biocompatibility, and cover broader chemical space.

MCE collected thousands of marketed/clinical kinase inhibitors, using their fragments for macrocyclization to generate derivatives. After evaluating synthetic accessibility and physicochemical properties, a million-scale virtual macrocyclic library was built for kinase-related virtual and AI-driven screening.

The discovery of hit molecule is a cornerstone of drug development. Among the diverse tools available, DNA-encoded libraries have emerged a revolutionary platform for high-throughput screening. Compared with traditional HTS, DEL features shorter screening processes, lower costs, simpler assays, and larger library capacities.

DEL Construction utilizes split-and-pool synthesis, a combinatorial chemistry approach that involves iterative splitting, reaction, and pooling. This strategy enables rapid, exponential assembly of fragments in minimal steps without the need for individual compound synthesis andassoicicated isolation or purification steps, thus greatly reducing overall costs. The technology enables simultaneous affinity screeningof massive compound collections to target proteins in a single step. By coupling chemical structures with unique DNA barcodes, each compound is tagged with a distinct DNA sequence for convenient tracking and decoding.DELs readily enable the construction and efficient screening of libraries containing millions to billions of compounds. As a result, DEL screening combines the dual advantages of high efficiency and low cost, making DEL a transformative technology in modern drug discovery.

The DEL kit consists of 50 independent libraries with a total scale of 100 billion compounds. It is constructed through stepwise combinatorial chemistry strategies involving 2-, 3-, and 4-round synthesis. By employing diverse scaffolds and flexible linking strategies, it encompasses various ring systems, linear frameworks, and heterocyclic structures. Screening can be achieved solely through affinity, independent of target-specific activity detection methods. This library is suitable for DEL screening against a wide range of targets.

MCE-18 stands for Medicinal Chemistry Evolution 2018, which was first published in Journal of Medicinal Chemistry in 2019 for assessing molecular novelty and three-dimensional complexity. Developed based on Clarivate global pharmaceutical patent database, this descriptor was constructed via big-data analysis covering 28,161 patented lead compounds, 1,370 approved drugs and nearly 30,000 preclinical-to-phase III drug candidates from 23 top pharmaceutical companies worldwide between 1950 and 2018, followed by structural clustering and removal of redundant outdated scaffolds for data denoising. Its scoring system integrates five core structural features including aromatic ring (AR), aliphatic heterocycle (NAR), chiral center (CHIRAL), spiro atom (SPIRO), cyclic and acyclic sp³ carbon ratio together with a quadratic topological correction factor. Breaking the limitations of the single Fsp³ parameter, MCE-18 effectively distinguishes conventional flat aromatic scaffolds from modern 3D-enriched novel chemotypes, overcoming typical drawbacks of traditional compound libraries such as scaffold redundancy, low screening hit rates and poor compatibility with allosteric and PPI-related difficult targets.

This library contains over 37,000 structurally diverse compounds with favorable overall drug-likeness, suitable for high-throughput screening against canonical targets including kinases, GPCRs and proteases as well as challenging allosteric and PPI targets. Compounds comply with the developmental trend of modern novel drug discovery, supporting routine primary screening as well as early hit identification of allosteric modulators and PPI inhibitors, serving as an efficient screening resource for early-stage innovative drug discovery.

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.