validation

Neurodegenerative diseases are incurable and life-threatening conditions that result in progressive degeneration and/or death of nerve cells. Some common neurodegenerative diseases include Alzheimer’s Disease (AD), Parkinson’s Disease (PD), Motor Neuron Disease (MND), Huntington’s Disease (HD), Spino-Cerebellar Ataxia (SCA), Spinal Muscular Atrophy (SMA), and Amyotrophic Lateral Sclerosis (ALS). Because the pathophysiology of neurodegenerative disorders is generally poorly understood, it is difficult to identify promising molecular targets and validate them. At the same time, about 85% of the drugs fail in clinical trials. Therefore, validating new targets and discovering new drugs to mitigate neurodegenerative disorders is need of the hour.

MCE offers a unique collection of 2,688 compounds with anti-Neurodegenerative Diseases activities or targeting the unique targets of neurodegenerative diseases. MCE Neurodegenerative Disease-related Compound Library is a useful tool for exploring the mechanism of neurodegenerative diseases and discovering new drugs for neurodegenerative diseases.

MCE Novel Bioactive Compound Library consists of 3,114 bioactive compounds with validated bioactivities tested by cell-based assays or biochemical assays. All compounds in this library are structurally novel and bioactivity diverse which makes it easier to discover new lead compounds. MCE Novel Bioactive Compound Library, as a supplement of MCE bioactive compound library (HY-L001), is a useful tool to screen new lead compounds.

Natural products are an attractive source with varied structures that exhibit potent biological activities, and desirable pharmacological profiles. The core scaffold of a natural product can also provide a biologically validated framework upon which to display diverse functional groups. Inspired by bioactive natural products, natural product-like compounds, occupying the same chemical space, are ideally suited to explore and to facilitate understanding of biological pathways.

MCE provides a unique collection of 649 natural product-like compounds that are structurally like Steroids, Tannins, Flavonoids, Quinones, Isoquinolines, etc. This library is an important source of lead compounds for drug discovery.

With features of enormous scaffold diversity and structural complexity, natural products (NPs) are the main sources of lead compounds and new drugs and play a highly significant role in the drug discovery and development process, especially for cancer and infectious diseases. A large number of natural products have been proven to have potential anti-tumor effects, mainly from plants, animals, Marine organisms and microorganisms. At present, derived than 60% of anti-tumor drugs come from natural sources, and they are widely used in breast, prostate and colon cancers.

MCE offers a unique collection of 1,745 natural products with validated anti-cancer activity. MCE anti-cancer natural product library is a useful tool for anti-tumor drugs screening and other related research.

According to reports, most known kinase inhibitors exert their effects through competitive binding in highly conserved ATP pockets. Although genetic techniques such as RNA interference can inactivate specific genes, most kinases are multi domain proteins, each of which has an independent function. Highly selective inhibitors have higher efficiency than non-selective inhibitors, and the selectivity to the target is at least 100 times higher. Therefore, ensuring the validation of targets with the most selective inhibitors is crucial for a more thorough understanding of the pharmacology of the kinase field. The Highly Selective Inhibitors Library contains 5,160 compounds, covering multiple targets and subtypes, such as GPCR protein family, Ion channel, multiple kinases, etc. The Highly Selective Inhibitors Library is an effective tool for screening different phenotypes

Antibacterial agents are a group of materials that fight against pathogenic bacteria. Thus, by killing or reducing the metabolic activity of bacteria, their pathogenic effect in the biological environments will be minimized. The most widely used antibacterial agents exert their effects on bacterial cell wall synthesis, protein synthesis, DNA replication and metabolic pathways. However, resistance to antimicrobial agents has become a major source of morbidity and mortality worldwide. The main mechanisms of resistance are limiting uptake of a drug, modification of a drug target, inactivation of a drug, and active efflux of a drug. Therefore, it is an urgent need to develop new drugs targeted at resistant organisms.

MCE offers a unique collection of 1,514 compounds with validated antibacterial activities. MCE antibacterial compound library is an effective tool for drug repurposing screening, combination screening and biological investigation.

Aging is an unavoidable process, leading to cell senescence due to physiochemical changes in an organism. Aging cells cease to divide and drive the progression of illness through various pathways, resulting in the death of an organism ultimately. Anti-aging activities are primarily involved in the therapies of age-related disorders such as Parkinson's Disease (PD), Alzheimer's Disease (AD), cardiovascular diseases, cancer, and chronic obstructive pulmonary diseases.

Natural products are known as effective molecules in anti-aging treatments, which delay the aging process through influencing several pathways and thus ensure an extended lifespan. MCE offers a unique collection of 193 natural products with validated anti-aging activity. MCE anti-aging natural product library is a useful tool for the study of aging-related diseases drugs and pharmacology.

Transcription is the essential first step in the conversion of the genetic information in the DNA into protein and the major point at which gene expression is controlled. Transcription of protein-coding genes is accomplished by the multi-subunit enzyme RNA polymerase II and an ensemble of ancillary proteins, called transcription factors (TFs). Transcription factors play an important role in the long-term regulation of cell growth, differentiation and responses to environmental cues. Deregulated transcription factors contribute to the pathogenesis of a plethora of human diseases, ranging from diabetes, inflammatory disorders and cardiovascular disease to many cancers, and thus these proteins hold great therapeutic potential.

MCE offers a unique collection of 1,606 compounds with validated transcription factor targets modulating properties. MCE transcription factor-targeted compound library is an effective tool for researching transcription factors as drug targets as well as modulation of TFs for different therapeutic applications.

A parasite is an organism that lives on or in a host organism and gets its food from or at the expense of its host. Parasites of humans include protozoans, helminths, and ecto-parasites (organisms that live on the external surface of a host). They are responsible for many diseases and are transmitted to their hosts most often through the ingestion of contaminated food, water or through the bite of an arthropod (e.g., a fly or tick), which can act as an intermediate host and as a vector. Parasitic diseases of humans are a major global health problem causing significant morbidity and mortality, especially in developing countries. Each year there are hundreds of millions of people infected with disease-causing parasites, particularly in tropical and subtropical regions of the world, resulting in an estimated one million deaths. Therefore, there is a dire need of novel anti-parasitic drugs.

MCE has a unique collection of 515 compounds with validated anti-parasitic activity which offer researchers an opportunity to screen novel anti-parasitic targets.

Natural products are an attractive source with varied structures that exhibit potent biological activities, and desirable pharmacological profiles. The core scaffold of a natural product can also provide a biologically validated framework upon which to display diverse functional groups. Inspired by bioactive natural products, natural product-like compounds, occupying the same chemical space, are ideally suited to explore and to facilitate understanding of biological pathways.

MCE 10K Natural Product-like Compound Library consists of 10,000 natural product-like compounds. Each compound has scaffold of natural products or Tanimoto coefficient >0.6 with natural products. The natural-likeness scoring of these compounds is >-2. What’s more, compounds in the library are drug-like and readily available for re-supply, making it a powerful tool for new drug research and development. It can be widely applied in high-throughput screening (HTS) and high-content screening (HCS).

Natural products are an attractive source with varied structures that exhibit potent biological activities, and desirable pharmacological profiles. The core scaffold of a natural product can also provide a biologically validated framework upon which to display diverse functional groups. Inspired by bioactive natural products, natural product-like compounds, occupying the same chemical space, are ideally suited to explore and to facilitate understanding of biological pathways.

MCE 5K Natural Product-like Compound Library consists of 5,000 natural product-like compounds. Each compound has scaffold of natural products or Tanimoto coefficient >0.6 with natural products. The natural-likeness scoring of these compounds is >-2. What’s more, compounds in the library are drug-like and readily available for re-supply, making it a powerful tool for new drug research and development. It can be widely applied in high-throughput screening (HTS) and high-content screening (HCS).

Angiogenesis is the physiological process through which new blood vessels are formed from pre-existing vessels. It occurs in various physiological processes e.g. embryonic development, menstrual cycle, exercise and wound healing etc. Angiogenesis is regulated by both endogenous activators and inhibitors. Some key activators of angiogenesis include vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), angiogenin, TGF-β, etc. whereas angiogenesis inhibitors are angiostatin, endostatin, interferon, platelet factor 4, etc. The loss of balance between these opposing signals leads to life threatening diseases like cancer, cardiovascular and ischemic diseases etc. which are thus controlled by exogenous angiogenesis activators (for cardiovascular/ischemic disorders) and inhibitors (for cancer).

MCE offers a unique collection of 2,446 compounds with validated angiogenesis targets modulating properties. MCE angiogenesis-related compound library is an effective tool for angiogenesis research and discovery of angiogenesis-related drugs.

The high rates of morbidity and mortality caused by fungal infections are associated with the current limited antifungal arsenal and the high toxicity of the compounds. Additionally, identifying novel drug targets is challenging because there are many similarities between fungal and human cells. The most common antifungal targets include fungal RNA synthesis and cell wall and membrane components, though new antifungal targets are being investigated. Nonetheless, fungi have developed resistance mechanisms, such as overexpression of efflux pump proteins, overexpression and changes in drug targets and biofilm formation, emphasizing the importance of discovering new antifungal drugs and therapies. Due to the limited antifungal arsenal, researchers have sought to improve treatment via different approaches, such as the combination of antifungal drugs, development of new formulations for antifungal agents and modifications to the chemical structures of traditional antifungals, etc.

MCE offers a unique collection of 406 compounds with validated antifungal activities. MCE antifungal compound library is an effective tool for drug repurposing screening, combination screening and biological investigation.

Mutations in oncogenes and tumor suppressor genes can modify multiple signaling pathways and in turn cell metabolism, which facilitates tumorigenesis. The paramount hallmark of tumor metabolism is “aerobic glycolysis” or the Warburg effect, coined by Otto Warburg in 1926, in which cancer cells produce most of energy from glycolysis pathway regardless of whether in aerobic or anaerobic condition. Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside. The increased uptake of glucose is facilitated by the overexpression of several isoforms of membrane glucose transporters (GLUTs). Likewise, the metabolic pathways of glutamine, amino acid and fat metabolism are also altered. Recent trends in anti-cancer drug discovery suggests that targeting the altered metabolic pathways of cancer cells result in energy crisis inside the cancer cells and can selectively inhibit cancer cell proliferation by delaying or suppressing tumor growth.

MCE provides a unique collection of 2,456 compounds which cover various tumor metabolism-related signaling pathways. These compounds can be used for anti-cancer metabolism targets identification, validation as well anti-cancer drug discovery.

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.

Recently, significant advancements in tyrosine-targeting electrophiles have primarily occurred in the field of protein-protein interactions (PPIs), where cysteine residues are often underrepresented and novel chemistries are needed to address these interfaces. In this context, tyrosines are frequently more accessible compared to more buried binding sites. Moreover, they are commonly found at "hot spots," which are functional epitopes of PPIs, with 12.3% of the residues consisting of tyrosines. This prevalence is likely due to the hydrophobic nature of tyrosine, its ability to participate in aromatic π-interactions, and its capacity for hydrogen bonding. Beyond PPIs, some progress has also been made in covalent tyrosine targeting in other areas where more commonly addressed side chains are lacking. Even though tyrosine has a slightly lower pKa value compared to the protonated lysine side chain (approximately 10 vs. 10.5 for the unprotected amino acid side chains), significantly less progress has been made in the development of tyrosine-targeted covalent ligands compared to lysine. This is likely due to the reduced flexibility of the tyrosine side chain and the greater steric hindrance of its hydroxy group, which makes it more challenging to adopt suitable reaction geometries.

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 124 fragment molecules which can target tyrosine residue and can be used for fragment-based covalent drug discovery.

In the research of covalent inhibitors targeting serine and threonine, scientists have found that the nucleophilicity of these hydroxyl groups is significantly enhanced due to the influence of their surrounding environment. This results in higher activity during catalytic reactions. Aspirin, which targets the non-catalytic domain serine (Ser529 in human COX1) of cyclooxygenase, exerts its anti-inflammatory effect through covalent binding. β-lactam antibiotics, which targets the catalytic domain serine of penicillin-binding proteins, interferes with bacterial cell wall synthesis.

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 3,300 fragment molecules which can target serine and threonine residues and can be used for fragment-based covalent drug discovery.

Targeted protein degradation(TPD) is a novel and promising approach to new drug discovery and development. It shows great potential for treating diseases with “undruggable” pathogenic protein targets and for overcoming drug resistance. Molecular glues and PROTACs are both targeted protein degraders that have attracted the most attention.

Molecular glues are small molecular degraders that mainly induce novel interaction between an E3 ligase and a target protein to form a ternary complex, leading to protein ubiquitination and subsequent proteasome degradation. Compared with PROTACs, molecular glues generally possess more favorable drug-like properties, such as lower MW, higher cell permeability, and better oral absorption. Molecular glues are emerging as a promising new therapeutic strategy.

MCE supplies a unique collection of 57 molecular glues which target various proteins. MCE Molecular Glue Compound Library is a useful tool to conduct scientific research and disease mechanism study.

The most prominent mechanism of action of kinase inhibitors is their competition with ATP by binding to the hinge region of the kinase protein. Once the kinase is blocked by an inhibitor, it loses the ability to transfer phosphate groups from ATP to other molecules, resulting in the loss of kinase activity.

The hinge-binding region of kinase inhibitors mimics the interaction pattern between the ATP nucleobase and the kinase. MCE extracted thousands of kinase inhibitors from the ChEMBL database and isolated their molecular fragments. In certain cases, the amino and amide groups on the molecular fragments are crucial for binding in the hinge region. Therefore, we enhanced the diversity of the collected results by adding these two groups to unoccupied positions on the ring system. Subsequently, the fragments were assessed for their hinge region binding ability via docking at distinct kinases, we also applied pharmacophore constraints to ensure interactions with key amino acids in the kinase hinge region, ultimately obtaining kinase-related molecular fragments.

MCE provides over 10,000 kinase fragment molecules that meet the above requirements and are available off the shelf, serving as an effective tool for screening and developing drugs targeting kinases.

Nucleoside and nucleotide analogues are synthetic, chemically modified compounds that have been developed to mimic their physiological counterparts in order to exploit cellular metabolism and subsequently be incorporated into DNA and RNA to inhibit cellular division and viral replication. In addition to their incorporation into nucleic acids, nucleoside and nucleotide analogues can interact with and inhibit essential enzymes such as human and viral polymerases (that is, DNA-dependent DNA polymerases, RNA-dependent DNA polymerases or RNA-dependent RNA polymerases), kinases, ribonucleotide reductase, DNA methyltransferases, purine and pyrimidine nucleoside phosphorylase and thymidylate synthase. These actions of nucleoside and nucleotide analogues have potential therapeutic benefits — for example, in the inhibition of cancer cell growth, the inhibition of viral replication as well as other indications.

MCE offers a unique collection of 551 nucleotide compounds including nucleotide, nucleoside and their structural analogues. MCE Nucleotide Compound Library is a useful tool to discover anti-cancer and antiviral drugs for high throughput screening (HTS) and high content screening (HCS).

Cancer is a multi-step process which involves initiation, promotion and progression. Chemical carcinogens can alter any of these processes to induce their carcinogenic effects. People are continuously exposed exogenously to varying amounts of chemicals that have been shown to have carcinogenic or mutagenic properties in experimental systems. Exposure can occur exogenously when these agents are present in food, air or water, and also endogenously when they are products of metabolism or pathophysiologic states such as inflammation. The administration of chemical carcinogens is one of the most commonly used methods to induce tumors in several organs in laboratory animals in order to study oncologic diseases of humans. MCE offers a unique collection of 134 chemical carcinogens which have been identified with carcinogenic activity either in humans or in animal models. MCE Tumorigenesis-Related Compound Library is a powerful tool for studying oncologic diseases of humans. Standard opration based on safety data sheet will not cause harm to the body.

Proteolysis-targeting chimera (PROTAC) has been developed to be a useful technology for targeted protein degradation. PROTACs consist of a ligand for E3 ligase (E3 ligase binder), a linker and a ligand (mostly small-molecule inhibitor) for protein of interest（target binder）. Upon binding to the target protein, the PROTACs can recruit E3 for target protein ubiquitination, which is subjected to proteasome-mediated degradation.

Although there are more than 600 E3 ubiquitin ligases, only several with small molecule ligands have been used for designing PROTACs, including Skp1-Cullin-F box complex containing Hrt1 (SCF), Von Hippel-Lindau tumor suppressor (VHL), Cereblon (CRBN), inhibitor of apoptosis proteins (IAPs), and mouse double minute 2 homolog (MDM2).

MCE carefully prepared a unique collection of 65 ligands for E3 ligase, which have been reported to be used in PROTAC design. MCE E3 ligase ligand library is a useful tool for PROTAC development.

Lipids are a diverse and ubiquitous group of compounds which have many key biological functions, such as acting as structural components of cell membranes, serving as energy storage sources and participating in signaling pathways. Several studies suggest that bioactive lipids have effects on the treatment of some mental illnesses and metabolic syndrome. For example, DHA and EPA are important for monoaminergic neurotransmission, brain development and synaptic functioning, and are also correlated with a reduced risk of cancer and cardiovascular disease in clinical and animal studies.

MCE supplies a unique collection of 1,523 lipid and lipid derivative related compounds including triglycerides, phospholipids, sphingolipids, steroids and their structural analogues or derivatives. MCE lipid compound library can be used for research in bioactive lipids, and high throughput screening (HTS) and high content screening (HCS).

Glycosides are compounds in which a sugar group is bonded through its anomeric carbon to another group via a glycosidic bond. Many biologically active compounds are glycosides. Glycosides comprise several important classes of compounds such as hormones, sweeteners, alkaloids, flavonoids, antibiotics, etc. The glycosidic residue can be crucial for their activity or can only improve pharmacokinetic parameters. Glycosides, which exhibit anti-inflammatory, anti-infection, anti-cancer and anti-oxidative properties, play numerous important roles in living organisms, such as streptomycin, as an aminoglycoside antibiotic, has anti-infection activity. Anthracyclines possess good antibacterial and anti-cancer activities.

MCE Glycoside Compound Library contains a unique collection of 795 glycoside compounds and is a useful tool to discovery glycoside drugs.

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

Macrocycles, molecules containing 12-membered or larger rings, are receiving increased attention in small-molecule drug discovery. The reasons are several, including providing access to novel chemical space, challenging new protein targets, showing favorable ADME- and PK-properties. Macrocycles have demonstrated repeated success when addressing targets that have proved to be highly challenging for standard small-molecule drug discovery, especially in modulating macromolecular processes such as protein–protein interactions (PPI). Otherwise, the size and complexity of macrocyclic compounds make possible to ensure numerous and spatially distributed binding interactions, thereby increasing both binding affinity and selectivity.

MCE offers a unique collection of 392 macrocyclic compounds which can be used for drug discovery for high throughput screening (HTS) and high content screening (HCS). MCE Macrocyclic Compound Library is a useful tool for discovering new drugs, especially for “undruggable” targets and protein–protein interactions.

Proteolysis-targeting chimera (PROTAC) has been developed to be a useful technology for targeted protein degradation. PROTACs consist of a ligand for E3 ligase (E3 ligase binder), a linker and a ligand (mostly small-molecule inhibitor) for protein of interest（target binder）. Upon binding to the target protein, the PROTACs can recruit E3 for target protein ubiquitination, which is subjected to proteasome-mediated degradation. Therefore, PROTACs execute their functions by degrading the target proteins rather than inhibiting them, which has a great superiority in overcoming resistance caused by target mutation or overexpression. To date, PROTAC technology has been applied to a variety of targets, including AR, ER, BTK, BET, and BCR-ABL to overcome resistance.

MCE carefully prepared a unique collection of 56 ligands for target proteins, which have been reported to be used in PROTAC design. MCE Target Protein Ligand Library is a useful tool for PROTAC development.

Covalent inhibitors are small molecules that can bind specifically to target proteins through covalent bonds and inhibit their biological functions. Although for a long time, covalent targeting has been playing a subordinate role in drug discovery, with an increasing number of reports on successful clinical applications of such drugs, the potential of these agents is now being acknowledged.

Covalent ligands rely on reactive groups (“warheads”), and new warheads are key to expanding the scope of covalent modalities. 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 8,900 fragment molecules with covalent modification potential, which can target various reactive amino acid residues and can be used for fragment-based covalent drug discovery.

Diabetes mellitus, usually called diabetes, is a group of metabolic disorders characterized by a high blood sugar level over a prolonged period of time. The most common types are Type I and Type II. Type I diabetes (T1D), also called juvenile onset diabetes mellitus or insulin-dependent diabetes mellitus, is characterized by destruction of the β-cells of the pancreas and insulin is not produced, whereas type II diabetes (T2D), also called non-insulin-dependent diabetes mellitus, is characterized by a progressive impairment of insulin secretion and relative decreased sensitivity of target tissues to the action of this hormone. Type 2 diabetes accounts for the vast majority of all diabetes mellitus. Diabetes of all types can lead to complications in many parts of the body and can increase the overall risk of dying prematurely. Possible complications include kidney failure, leg amputation, vision loss and nerve damage.

The pathogenesis of diabetes is complicated, and development of the safe and effective drugs against diabetes is full of challenge. Increasing studies have confirmed that the pathogenesis of diabetes is related to various signaling pathways, such as insulin signaling pathway, AMPK pathway, PPAR regulation and chromatin modification pathways. These signaling pathways have thus become the major source of the promising novel drug targets to treat metabolic diseases and diabetes.

MCE Anti-diabetic Compound Library owns a unique collection of 839 compounds, which mainly target SGLT, PPAR, DPP-4, AMPK, Dipeptidyl Peptidase, Glucagon Receptor, etc. This library is a useful tool for discovery anti-diabetes drugs.

Antibody-Drug Conjugates (ADCs), a new class of treatment for cancer, are composed with a monoclonal antibody, a linker and a cytotoxic agent also referred to as a payload. To date, several ADCs have received market approval and more than 60 ADCs are currently in clinical trials. ADCs are one of the fastest growing classes of oncology drugs worldwide.

The payload or cytotoxic agent is the most important unit in the ADC. ADC has the capability to kill cancer cell depending on the potency of the payload. MCE provides 107 highly potent cytotoxins that contain auristatin derivatives, maytansinoids, calicheamicin, duocarmycin, pyrrolobenzodiazepines (PBDs), etc.

Animal disease models are used in a variety of settings in basic research, such as studies on mechanisms of disease progression and evaluation new drugs. Animal models can be broadly classified into five categories: 1) experimental, 2) spontaneous, 3) negative, 4) orphan, 5) genetically engineered. Experimental models, which are induced artificially in the laboratory, are most common. Some small molecular compounds are usually used as inducers for animal models, such as Ceruletide for inflammatory model, Azoxymethane for tumor model. These inducers are useful tool in building animal models.

MCE offers a unique collection of 51 animal model inducers, involving inflammatory model, tumor model, nervous disease model, etc. MCE Animal Disease Model library is a powerful tool for the establishment of animal disease models.

Peptides are a group of biologically active substances that are involved in various cellular functions of organisms. Peptides are often used in functional analysis, vaccine research and especially in the field of drug research and development. At present, more than 80 peptide drugs have reached the market for a wide range of diseases, including diabetes, cancer, osteoporosis, multiple sclerosis, HIV infection and chronic pain.

MedChemExpress (MCE) offers a comprehensive collection of 1,730 peptides, including bioactive peptides, amino acid derivatives, and blocking peptides. MCE Peptide Library can be used for peptide library screening, peptide drug discovery, vaccine development, target verification, structural activity research, etc.

A drug metabolite is a byproduct of the body breaking down, or “metabolizing” a drug into a different substance. Most drugs undergo chemical alteration by various bodily systems as a way to create compounds that are more easily excreted from the body. Drugs can be metabolized by oxidation, reduction, hydrolysis, hydration, conjugation, condensation, or isomerization. Drug metabolism can produce metabolites with physicochemical and pharmacological properties that differ substantially from those of the parent drug, and consequently have important implications for both drug safety and efficacy.

MCE offers a unique collection of 263 drug metabolites which is a useful tool for drug safety and efficacy study and drug repurposing.

The lack of availability of appropriate medicines for children is an extensive and urgent problem. A variety of obstacles hinder children's drug development, including the limited commercial interest, lack of suitable infrastructure and competence for conducting paediatric clinical trials, difficulties in trial design, ethical worries and many others. Because of these factors, unlicensed and off-label prescribing is very common in children which may lead to safety concern.

MCE offers a unique collection of 692 Pediatric medicines, all of which have been approved or studied in clinical trials for children diseases. MCE children’s drug library is a useful tool for drug repurposing to discover new children’s indications.

Chemical probes are simply reagents with high potency, selectivity and cell-permeability which play important roles in both fundamental and applied biological research. In their most common application, chemical probes can establish the tractability of a specific target. They are used to interrogate the relationship between a target and its phenotype (biological tractability) as well as an ability to modulate that phenotype using a small molecule. Otherwise, chemical probes also have had a major impact in enabling and accelerating discoveries along the path to pioneer medicines. They have helped to improve the understanding of targets and pathways and have created opportunities for proprietary drug discovery efforts to an extent that would not have been possible otherwise.

MCE provides a unique collection of 279 chemical probes with high potency (at least 100 nM potency), selectivity (at least 10-fold selectivity against any other target) and cell-permeability (at least 10 μM potency). MCE Chemical probe library is a useful tool for target identification and mechanism research.

Food additives are substances added to food to maintain or improve its safety, freshness, taste, texture, or appearance. All food additives used in food undergo a safety assessment, which includes rigorous testing, before they are approved, so all food additives are generally recognized as safe substances.

MCE supplies 446 approved food additives which are safe substances and can be used for drug discovery and other research.

Flavor is an expression of smell and taste that is achieved through a variety of chemical processes triggered by molecules. Food flavor is an important attribute of food quality and in some cases determines consumers' food preferences. In addition to playing a key role in taste and smell, flavor molecules can also be involved in regulating metabolism and have an impact on health. In daily life, flavor molecules have absolute application value in food and spices. In scientific research, the study of flavor molecules is helpful to reveal the relationship between food intake and taste perception. Research on the combination behavior of flavor and food components can explore the retention, release and perception of flavor molecules. Most importantly, while exploring multi-sensory flavor perception, the food industry can fully mobilize the enthusiasm of researching new strategies for delicious and healthy food design.

Based on the FlavorDB database, collects and organizes 414 flavor molecules, which can be used in taste perception and other related studies.

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 212 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.

Copper is an important co-factor of all biological enzymes, but if the concentration exceeds the threshold of maintaining the homeostasis mechanism, copper will lead to cytotoxicity. This death mechanism has been named "Cuproptosis".

The mechanism of cuproptosis distinct from all other known mechanisms of regulated cell death, including apoptosis, pyroptosis, necroptosis, and ferroptosis.

Copper combine with the lipoylated components of the tricarboxylic acid cycle (TCA), leading to lipoylated protein aggregation and subsequent loss of iron-sulfur cluster proteins, ultimately resulting in protein toxicity stress and cell death. Studies have shown that the necessary factors for cuproptosis include the presence of glutathione, mitochondrial metabolism of galactose and pyruvate, and glutamine metabolism.

Targeted regulation of cuproptosis is a potential choice to treat cancer, rheumatoid arthritis, and other diseases. For example, up-regulation of LIPT1 may inhibit the occurrence and development of tumors by destroying TCA in mitochondria and then inducing cuproptosis.

MCE supplies a unique collection of 246 cuproptosis-related compounds, all of which act on the targets or signaling pathways related to cuproptosis and may have in inhibitory or activated effect on cuproptosis. MCE Cuproptosis Library is a useful tool for drug research related to cancer, rheumatoid arthritis, and other diseases.

Tuberculosis (TB), usually caused by bacteria (Mycobacterium tuberculosis), is an infectious disease that mainly affects the lungs. According to the statistics of the World Health Organization (WHO), 10 million people suffer from tuberculosis every year, and 1.5 million people die of tuberculosis every year, which makes tuberculosis the number one killer of infectious diseases.

Tuberculosis can be cured through the standard 6-month course of treatment of four kinds of antibiotics. Common drugs include rifampicin and isoniazid. In some cases, TB bacteria do not respond to standard drugs, that is, patients with drug-resistant tuberculosis. The treatment of drug-resistant tuberculosis takes longer and is more complex. In the face of the resurgence of tuberculosis in the world and the rapid emergence of multi drug resistant tuberculosis, it is very important to develop new anti-tuberculosis drugs or new clinical treatment schemes for existing anti mycobacterium drugs.

MCE supplies a unique collection of 115 compounds with clear anti-tuberculosis activity. MCE Anti-tuberculosis Compound Library is a useful tool for anti-tuberculosis related research and anti-tuberculosis drug development

An inactive ingredient is any component of a drug product other than the active ingredient. Inactive ingredients are added during the manufacturing process of pharmaceutical products such as tablets, capsules, suppositories, and injections. In new drug development, once an inactive ingredient has appeared in an approved drug product for a particular route of administration, the inactive ingredient is not considered new and may require a less extensive review the next time it is included in a new drug product.

MCE offers a unique collection of 170 inactive ingredients, which only contain inactive ingredients of the final dosage forms of the drug. MCE Inactive Ingredient library is a powerful tool for aiding in the development of the drug and saving unnecessary time.

The TCA cycle (tricarboxylic acid cycle)—is also known as the Krebs cycle or the citric acid cycle (CAC). The TCA cycle is a series of chemical reactions that release stored energy through the oxidation of acetyl-CoA in carbohydrates, fats, and proteins.

For decades, the TCA cycle has been considered as the central pathway for cell oxidative phosphorylation to produce energy and biosynthesis. Research shows that TCA cycle is associated with many diseases, especially cancer. In colon carcinoma, liver cancer and other cancers, there are mutations that lead to the imbalance of TCA cycle metabolites, indicating that TCA cycle may be related to the occurrence of cancer. Understanding the role and molecular mechanism of TCA cycle in inhibiting or promoting cancer progression will promote the development of new metabolite-based cancer treatment methods in the future.

MCE supplies a unique collection of 67 compounds related to the TCA cycle. MCE TCA Cycle Compound Library is a useful tool for the TCA cycle related research and anti-cancer drug development.

Covalent inhibitors are small molecules that can bind specifically to target proteins through covalent bonds and inhibit their biological functions. Although for a long time, covalent targeting has been playing a subordinate role in drug discovery, with an increasing number of reports on successful clinical applications of such drugs, the potential of these agents is now being acknowledged. Currently, cysteine is the most common covalent amino acid residue in a variety of covalent drugs, and various warheads have been developed that can react with cysteine, providing the key building blocks for covalent drugs to form covalent bonds.

To meet the development needs of covalent inhibitors targeting cysteine, MCE has designed a unique collection of 3,321 fragments with different covalent warheads that target cysteine. The MCE Cysteine Targeted Covalent Fragment Library is designed using the following covalent warheads: Acrylamides, Propiolic acid ester, Dimethylamine functionalized acrylamides, Chloroacetamides, Acrylonitrile, 2-Cyanoacrylamide, Aziridine, Haloacetamide, etc. All fragments are pre-filtered with the Rule of Three restrictions which can be used for fragment-based covalent drug development.

Mitochondrial autophagy refers to the selective encapsulation and degradation of damaged mitochondria by cells through the autophagy mechanism, thereby maintaining mitochondrial and cellular homeostasis. The concept of mitochondrial autophagy has received extensive attention since it was proposed. Current studies have shown that the mechanisms of mitochondrial autophagy can generally be divided into two categories: Ubiquitin-dependent pathways and Ub-independent pathways. In addition, mitochondrial autophagy is a research hotspot related to the pathogenesis of neurodegenerative diseases, cardiovascular diseases, cancer, metabolic diseases and other clinical diseases. Therefore, high-throughput screening based on mitochondrial autophagy can effectively screen out compounds that are closely related to the occurrence of diseases and analyze their mechanisms.

MCE can provide a library of 678 mitophagy compounds, which can be used for drug development and mechanism research in cancer, immunity, infection and other hot research fields.

Increasing research have shown that Traditional Chinese Medicine (TCM) possess antiviral activities against various viral strains, such as herpes simplex virus, influenza virus, hepatitis B and C viruses, and SARS-CoV. To date, dozens of Chinese herbs and hundreds of natural TCM ingredients have been reported to exhibit good antiviral activities. Active components from TCM are one of the important sources for antiviral drugs discovery.

MCE designs a unique collection of 171 active compounds of antiviral Chinese Herbal Medicines. MCE Antiviral Traditional Chinese Medicine Active Compound Library is a useful tool for discovery antiviral drugs from TCM.