function

Glycomimetics are designed to mimic the structure of natural carbohydrates and modulate their disease-related functions. Macrocyclic glycomimetics are an extremely interesting class of glycomimetics as they occupy space between small and macro molecules. Macrocyclic glycomimetics are mostly represented by naturally occurring molecules derived from marine microorganisms and bacterial or fungal metabolites.

Macrophages are effector cells of the innate immune system, engulfing bacteria and secreting pro-inflammatory and antibacterial mediators. They are an important component of the first line defense against pathogens and tumor cells. In addition, macrophages play an important role in eliminating damaged cells through programmed cell death. Like all immune cells, macrophages originate from pluripotent hematopoietic stem cells in the bone marrow. Macrophages play key functions in many physiological processes beyond homeostasis and innate immunity, including metabolic function, cell debris clearance, tissue repair, and remodeling. In order to fulfill their different functional roles, macrophages can polarize into a series of phenotypes, including classic (pro inflammatory, M1) and alternative (anti-inflammatory, healing promoting, M2) activation states, as well as a wide range of regulatory phenotypes and subtypes. Macrophages exist in all vertebrate tissues and have a dual function in host protection and tissue damage, maintaining a good balance.

MCE designs a unique collection of 158 macrophage related compounds. It is a good tool to be used for research on Inflammation, cancer and other diseases.

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 1,363 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).

Dopamine receptor (DAR), widely distributed in the brain, plays a key role in regulating motor function, motivation, driving force and cognition. The role of DA is mediated by D1-type (D1, D5) and D2-type receptors (D2S, D2L, D3, D4), which are distributed in presynaptic, postsynaptic and extrasynaptic, projection neurons and interneurons. Each receptor has a different function. D1 and D5 receptors couple with G stimulation sites and activate Adenylyl cyclase. The activation of Adenylyl cyclase leads to the production of the second messenger cAMP, which leads to the production of protein kinase A (PKA), which leads to further transcription in the nucleus. D2 to D4 receptors are coupled to G inhibitory sites to inhibit adenylyl cyclase and activate potassium Ion channel. These receptors utilize phosphorylation cascades or direct membrane interactions to affect the functions of voltage-gated and neurotransmitter-gated channels, cytoplasmic enzymes, and transcription factors. Dopamine receptor plays an important role in daily life.

MCE designs a unique collection of 199 small molecules related to dopamine receptor. It is a good tool for screening drugs from nervous system disease.

Normal mitochondrial function is critical for maintaining cellular homeostasis because mitochondria produce ATP and are the major intracellular source of free radicals. Cellular dysfunctions induced by intracellular or extracellular insults converge on mitochondria and induce a sudden increase in permeability on the inner mitochondrial membrane, the so-called mitochondrial membrane permeability transition (MMPT). MMPT is caused by the opening of pores in the inner mitochondrial membrane, matrix swelling, and outer membrane rupture. The MMPT is an endpoint to initiate cell death because the pore opening together with the release of mitochondrial cytochrome c activates the apoptotic pathway of caspases.

The normal operation of mitochondrial function is important for maintaining normal cell death and treatment of mitochondrial diseases. MCE offers a unique collection of 588 compounds with identified and potential mitochondrial protective activity. MCE Mitochondrial Protection Compound Library is critical for drug discovery and development.

Immunity refers to the ability of the body to resist the invasion of pathogenic microorganisms and resist a variety of diseases. Immunocompromised will inevitably lead to a series of diseases. Immunopotentiator are a class of compounds that enhance immune function and induce immune response. Immunopotentiator can activate the proliferation and differentiation of one or more kinds of immune active cells in the body, promote the secretion of lymphocytes, and then enhance the immune function of the body. Immunopotentiator are mainly used in the treatment of tumors, infectious diseases and immunodeficiency diseases. In addition, immunopotentiator are often used as adjuvants in combination with vaccine antigens to enhance the immunogenicity of vaccines.

MCE designs a unique collection of 82 compounds with definite or potential Immunopotentiating effect, mainly targeting the NOD-like Receptor (NLR), Toll-like Receptor (TLR), NF-κB, etc. It is an effective tool for development and research of anti-cancer, anti-infectious diseases and anti-immunodeficiency diseases compounds.

Antibiotics are types of antimicrobial products used for the treatment and prevention of bacterial infections. Antibiotics can kill or inhibit bacterial growth. Although the target of an antibiotic is bacteria, some antibiotics also attack fungi and protozoans. However, antibiotics rarely have an effect on viruses. The major mechanism underlying antibiotics is the inhibition or regulation of enzymes involved in cell wall biosynthesis, nucleic acid metabolism and repair, protein synthesis, or disruption of membrane structure. Many of these cellular functions targeted by antibiotics are most active in multiplying cells. Since there is often overlap in these functions between prokaryotic bacterial cells and eukaryotic mammalian cells, it is not surprising that some antibiotics have also been found to be useful as anticancer agents.

MCE supplies a unique collection of 638 antibiotics, including penicillins, cephalosporins, tetracyclines, macrolides, etc. MCE Antibiotics Library is a useful tool for anti-bacterial or anti-cancer drugs discovery.

The endocrine system is a chemical messenger system comprising feedback loops of the hormones released by internal glands of an organism directly into the circulatory system, regulating distant target organs. Hormones are chemicals that serve to communicate between organs and tissues for physiological regulation and behavioral activities. Hormones affect distant cells by binding to specific receptor proteins in the target cell, resulting in a change in cell function.

The endocrine system is concerned with the integration of developmental events proliferation, growth, and differentiation, and the psychological or behavioral activities of metabolism, growth and development, tissue function, sleep, digestion, respiration, excretion, mood, stress, lactation, movement, reproduction, and sensory perception caused by hormones. Irregulated hormone release, inappropriate response to signaling or lack of a gland can lead to endocrine disease.

MCE offers a unique collection of 874 endocrinology related compounds targeting varieties of hormone receptors such as thyroid hormone receptor, TSH receptor, GNRH receptor, adrenergic receptor, etc. MCE Endocrinology Compound Library is a useful tool for the discovery of endocrinology drugs.

Medicine Food Homology (MFH) means that some food themselves are medicines and there is no absolute boundary between them. MFH theory combines the function of food and medicine together scientifically and MFH materials can be used both for food and medicine. Besides nutritional value, MFH materials also have the functions in the prevention and treatment of disease and many other healthcare effects. Food as medicines has many benefits because of their safety while taking drugs will bring inevitable side effect to people. In order to ensure the safe use of functional food, National Health Commission of People's Republic of China made specific provisions on MFH items. More than 100 kinds of widely used MFH materials have been released.

Based on MFH items released by National Health Commission, PRC, MCE carefully designs a unique collection of 1,717 Medicine Food Homology Compounds with high safety that can be used for high throughput and high content screening for drug discovery.

Endoplasmic reticulum (ER) contributes to the production and folding of approximately one third of cellular proteins, and is thus inextricably linked to the maintenance of cellular homeostasis and the fine balance between health and disease. However, some adverse factors negatively impact ER functions and protein synthesis, resulting in the activation of Endoplasmic reticulum stress (ER stress, ERS) and unfolded protein response (UPR) signaling pathways. The UPR is triggered when ER protein folding capacity is overwhelmed by cellular demand and the UPR initially aims to restore ER homeostasis and normal cellular functions. However, if this fails, then the UPR triggers cell death. Chronic ER stress and defects in UPR signaling are emerging as key contributors to a growing list of human diseases, including diabetes, neurodegeneration and cancer.

MCE Endoplasmic Reticulum Stress Compound Library contains 221 ER stress-related compounds that mainly target PERK, IRE1, ATF6, etc. MCE ER stress library is a useful tool for researching ER stress and related diseases.

Mitochondria, as the main place of energy supply in life, is essential to maintain normal life activities. Mitochondrial dysfunction is associated with common diseases, such as cardiovascular diseases, neurodegenerative diseases, diabetes and cancer. The heart, brain and liver rely heavily on mitochondrial function as the main organs for drug metabolism. In addition, mitochondria is also a target of many drugs, some of which induce organotoxicity by inducing mitochondrial toxicity.

MCE contains 472 mitochondrial toxic compounds, which can be used as tool compounds for drug development and disease mechanism research.

Epigenetics refers to changes in phenotype that are not rooted in DNA sequence. Many types of epigenetic processes have been identified, including DNA methylation, alteration in the structure of histone proteins and gene regulation by small noncoding microRNAs. Modification of DNA, protein, or RNA, resulting in changes to the function and/or regulation of these molecules, without altering their primary sequences, reveals the complexities of cellular differentiation, embryology, the regulation of gene expression, aging, cancer, and other diseases.

MCE provide a unique collection of 1,249 epigenetics-related compounds that can be used in the research of the related diseases.

Neurotransmitters are chemical messengers that allows a neuron's electrical signal to pass to a postsynaptic neuron or effect target. Neurotransmitters include amino acids, monoamines, and peptides, while other neurotransmitters are composed of metabolites such as nitric oxide and carbon monoxide. The function of neurotransmitters is closely related to the disease of life, helping to regulate the body's heartbeat, blood pressure, breathing, sleep, aging and muscle activity. Therefore, research based on neurotransmitters can help to increase human understanding of diseases.

MCE collects and organizes 53 neurotransmitters and is a tool library for drug screening and mechanism research.

Ferroptosis is a novel type of cell death program that is distinct from apoptosis, necroptosis and autophagy. It is dependent on iron and reactive oxygen species (ROS) and is characterized by lipid peroxidation. As a novel type of cell death, ferroptosis has distinct properties and recognizing functions involved in physical conditions or various diseases including cancers, neurodegenerative diseases, acute renal failure, etc.

MCE carefully collected a unique collection of 938 ferroptosis signaling pathway related compounds with ferroptosis-inducing or -inhibitory activity. MCE Ferroptosis Compound Library is a useful tool to study ferroptosis mechanism as well as related diseases.

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 1,376 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.

Antibody inhibitors are compounds with the same activity as the original therapeutic antibodies, which can be used as positive controls for drug efficacy evaluation and other studies. Antibody inhibitors can also assist in verifying the functional activity of the target protein. These antibody inhibitors are active in vivo and can achieve certain physiological functions by blocking or neutralizing target proteins, such as CD20, HER2, EGFR, VEGFR, TNF-α, etc. In drug screening, antibody inhibitor-based screening can be carried out to identify active compounds targeting target proteins and target diseases.

MCE can provide 21 antibody inhibitors that can be used for drug development in cancer, immunity, infection and other hot research areas.

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 4,694 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

A membrane protein is a protein molecule that is attached to or associated with the membrane of a cell or an organelle. Membrane proteins can be classified into two groups based on how the protein is associated with the membrane: integral membrane proteins and peripheral membrane proteins. In humans, about 30% genome encodes membrane proteins. Membrane proteins perform a variety of functions vital to the survival of organisms, for example, signal transduction, molecules or ion transportation, enzymatic catalysis, and intercellular communication. Membrane proteins also play important roles in drug discovery. As reported, more than 60% of current drug targets are membrane proteins.

MCE supplies a unique collection of 6,927 compounds targeting a variety of membrane proteins. MCE Membrane Protein-targeted Compound Library can be used for membrane protein-focused screening and drug discovery.

The blood-brain barrier (BBB) is the complex network of brain microvessels. It protects the brain from the external bloodstream environment and supplies the brain with the required nutrients for normal function. However, blood-brain barrier is also the obstacle to deliver beneficial drugs to treat CNS (central nervous system) diseases or brain tumors, as it has the least permeable capillaries in the entire body due to physical barriers (tight junctions). Therefore, it is crucial to discover drugs which can cross this barrier for the treatment of brain-based diseases, such as Alzheimer’s disease (AD), Parkinson’s disease (PD) and epilepsy.

MCE offers a unique collection of 858 compounds with confirmed CNS-Penetrant property. It’s a useful tool for the discovery of drugs used for brain diseases, such as brain tumors, mental disorders, and neurodegenerative diseases.

Lipids are a fundamental class of organic molecules implicated in a wide range of biological processes, and based on this can be broadly classified into five categories: fatty acids, triacylglycerols (TAGs), phospholipids, sterol lipids and sphingolipids. Lipids play a crucial role in different metabolic pathways and cellular functions. Lipid metabolism is an important physiological process that is related to nutrient adjustment, hormone regulation, and homeostasis. Lipid metabolism dysregulation is associated with many diseases such as obesity, liver disease, aging and inflammation.

MCE offers a unique collection of 656 compounds related to lipid metabolism, which target relevant targets in the process of lipid metabolism, such as ATGL, MAGL, FAAH, acetyl-Coa Carboxylase, FASN, etc. MCE lipid metabolism compound library is a useful tool for research lipid metabolism and drug discovery of diseases related to lipid metabolism.

Metabolism is the set of life-sustaining chemical reactions in organisms that maintain cell homeostasis. Metabolic pathways are enzyme-mediated biochemical reactions that lead to biosynthesis (anabolism) or breakdown (catabolism) of molecules including glucose metabolism, lipid metabolism and amino acid or protein metabolism within a cell or tissue. As catalysts, enzymes are crucial to metabolism as they allow a reaction to proceed more rapidly and tregulate the rate of a metabolic reaction. Due to the importance of metabolic balance in the organism, the abnormal function of metabolic enzymes often leads to the occurrence of a variety of metabolic diseases, such as diabetes, obesity, cardiovascular disease, etc.

MCE designs a unique collection of 2,861 metabolic enzymes related small molecules, which is an important tool for studying the metabolic activities of organisms and developing drugs for metabolic diseases.

Kinase is an enzyme that adds phosphate groups to other molecules. This process is known as phosphorylation. Protein phosphorylation is a key aspect in the regulation of a large number of cellular processes including cellular division, metabolism, signal transduction, and so on. There are over 500 kinases encoded by the human genome and it has been estimated that kinases regulate approximately 50% of cellular functions. Kinases are a large group of drug targets in drug discovery. Kinase inhibitors are an important class of drugs that block certain enzymes involved in diseases such as cancer and inflammatory disorders.

Kinase inhibitor library designed by MCE contains 2,673 kinase inhibitors and regulators mainly targeting protein kinases (VEGFR, EGFR, BTK, CDK, Akt, etc.), lipid kinases (PI3K, PI4K, SK, etc.) and carbohydrate kinases (Hexokinase), and is a useful tool for kinase drug discovery and related research.

Accumulating evidence has revealed that intestinal microbiota play an important role in human health and disease, including cardiovascular diseases, inflammatory bowel disease, diabetes, obesity, cancer, and depression, etc. Changes in the composition of gut microbiota associated with disease, referred to as dysbiosis, have been linked to pathologies. Indeed, the gut microbiome functions like an endocrine organ, generating bioactive metabolites which play important roles in human metabolism, health, and disease. Gut microbiome has become a novel therapeutic target for many diseases. Analysis and identification of gut microbial metabolite will contribute to the development of therapeutic methods.

In order to meet the need of gut microbiome research, MCE carefully selected a unique collection of 502 gut microbial metabolites. MCE gut microbial metabolite library is a powerful tool for gut microbiome research and gut microbiome -related drug discovery.

Human metabolism is an integral part of cellular function that reflects individual differences in health, disease, diet, and lifestyle. Many health conditions such as obesity, diabetes, hypertension, heart disease, and cancer are associated with abnormal metabolic states. In the pathological state of the human body, metabolic pathways are significantly altered, resulting in aberrant levels of intermediates or end-products that can be viewed as potential diagnostic biomarkers or even therapeutic targets. Therefore, detection, identification and quantification of human metabolites are very important for drug metabolism research in drug development.

MCE offers a unique collection of 5,990 human metabolites, including endogenous metabolites and exogenous metabolites, covering multiple structure types, such as lipids, amino acids, nucleic acids, carbohydrates, organic acids, biogenic amines, vitamins,. MCE Human Metabolites Library is a helpful tool for studying the relationship between diseases and metabolism.

Protein serine/threonine kinases (PSKs) are protein kinases that use ATP as a high-energy donor molecule to transfer phosphate groups to serine/threonine residues of target protein. As an important signal transduction regulator, serine/threonine kinases can affect the function of target proteins by disrupting enzyme activity or binding of target proteins to other proteins. Serine/threonine kinases are involved in the regulation of immune response, cell proliferation, differentiation, apoptosis and other physiological processes. Serine/threonine kinase inhibitors are an important class of compounds that have been widely studied in cancer, chronic inflammation, autoimmune diseases, aging and other diseases.

MCE designs a unique collection of 1,286 serine/threonine kinase inhibitors, mainly targeting the receptor PKA, Akt, PKC, MAPK/ERK, etc, which is an effective tool for development and research of anti-cancer, anti-chronic inflammatory diseases, anti-autoimmune diseases and anti-aging compounds.

The cytoskeleton is responsible for contraction, cell motility, movement of organelles and vesicles through the cytoplasm, cytokinesis, intracellular signal transduction, and many other functions that are essential for cellular homeostasis and survival. It accomplishes these tasks through three basic structures: F-actin, microtubules, and intermediate filaments (IFs). The cytoskeleton is a dynamic structure where the three major filaments and tubules are under the influence of proteins that regulate their length, state of polymerization, and level of cross-linking. Since cytoskeleton is involved in virtually all cellular processes, cytoskeletal protein aberrations are the underlying reason for many pathological phenotypes, including several cardiovascular disease syndromes, neurodegeneration, cancer, liver cirrhosis, pulmonary fibrosis, and blistering skin diseases.

MCE designs a unique collection of 1,276 cytoskeleton-related compounds mainly focusing on the key targets in the cytoskeleton signal pathway and can be used in the research of cytoskeleton signal pathway and related diseases.

Fragment-based drug discovery (FBDD) is well suited for discovering both drug leads and chemical probes of protein function; it can cover broad swaths of chemical space and allows the use of creative chemistry. Fragment-based drug discovery is well-established in industry and has resulted in a variety of drugs entering clinical trials, with two, vemurafenib and venetoclax, already approved. FBDD also has key attractions for academia. Notably, it is able to tackle difficult or novel targets for which no chemical matter may be found in existing HTS collections.

MCE designs a unique collection of 22,464 fragment compounds, all of which obey a heuristic rule called the “Rule of Three (RO3) ”, in which molecular weight ≤300 Da, the number of hydrogen bond donors (H-donors) ≤3, the number of hydrogen bond acceptors (H-acceptors) is ≤3 and cLogP is ≤3. This library is an important source of lead-like drugs.

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 4,528 compounds with different covalent warheads that target cysteine. The MCE Cysteine Targeted Covalent Library is designed using the following covalent warheads: Acrylamides, Propiolic acid ester, Dimethylamine functionalized acrylamides, Chloroacetamides, Acrylonitrile, 2-Cyanoacrylamide, Aziridine, Haloacetamide, etc.

Protein tyrosine kinases (PTKs) are key signaling molecules and important drug targets. Two classes of PTKs are present in cells: the transmembrane receptor PTKs (RTKs) and the nonreceptor PTKs. The RTK family includes the receptors for insulin and for many growth factors, such as EGFR, FGFR, PDGFR, VEGFR, and NGFR. RTKs are transmembrane glycoproteins that are activated by the binding of their ligands, and they transduce the extracellular signal to the cytoplasm by phosphorylating tyrosine residues on the receptors themselves (autophosphorylation) and on downstream signaling proteins. Their principal functions of PTKs involve the regulation of multicellular aspects of the organism. Cell to cell signals concerning growth, differentiation, adhesion, motility, and death are frequently transmitted through tyrosine kinases. In humans, tyrosine kinases have been demonstrated to play significant roles in the development of many disease states, including diabetes and cancers.

MCE designs a unique collection of 1,064 compounds that act as a useful tool for PTKs-related drug screening and disease research.

Autoimmune disease is a pathological disease characterized by inflammatory disorders targeting autoantigens. The routine treatment of autoimmune diseases suppresses general immune function to regulate uncontrolled inflammation. The current targeted immunotherapy suppresses the main pro-inflammatory signaling pathways by blocking inflammatory cytokines, cell surface molecules, and intracellular kinases. As key participants in innate immunity, macrophages and dendritic cells (DCs) are crucial for Ag presentation and pro-inflammatory cytokine production, such as TNF and IL-1 β、 IL-6, IL-23, B cell activating factor (BAFF), and the proliferation-inducing ligand (APRIL, also known as TNFSF13A).

MCE designs a unique collection of 461 autoimmune disease-related compounds, covering multiple targets and subtypes, such as TNF Receptor, IFNAR, JAK, Btk, TLR, IL-6, IL-17, IL-23, etc. It is a useful tool for screening autoimmune disease drugs.

DNA is prone to numerous forms of damage that can injure cells and impair fitness. Cells have developed an array of mechanisms to repair these injuries. Proliferating cells are especially vulnerable to DNA damage due to the added demands of cellular growth and division. Cell cycle checkpoints represent integral components of DNA repair that coordinate cooperation between the machinery of the cell cycle and several biochemical pathways that respond to damage and restore DNA structure. By delaying progression through the cell cycle, checkpoints provide more time for repair before the critical phases of DNA replication, when the genome is replicated, and of mitosis, when the genome is segregated. Loss or attenuation of checkpoint function may increase spontaneous and induced gene mutations and chromosomal aberrations by reducing the efficiency of DNA repair.

MCE owns a unique collection of 2,037 cell cycle/DNA damage-related compounds which can be used in the research of the same.

Flavonoids are an important class of natural products; particularly, they belong to a class of plant secondary metabolites having a polyphenolic structure, widely found in fruits, vegetables and certain beverages. Flavonoids can be subdivided into different subgroups depending on the carbon of the C ring on which the B ring is attached and the degree of unsaturation and oxidation of the C ring. These subgroups are: flavones, flavonols, flavanones, flavanonols, flavanols or catechins, anthocyanins and chalcones. Flavonoids are now considered as an indispensable component in a variety of nutraceutical, pharmaceutical, medicinal and cosmetic applications. This is attributed to their anti-oxidative, anti-inflammatory, anti-mutagenic and anti-carcinogenic properties coupled with their capacity to modulate key cellular enzyme function. Naturally occurring flavonoids are known to have biological activities for use as drugs, for example, in diseases like cancer, Alzheimer’s disease (AD), atherosclerosis, etc.

MCE offers a unique collection of 519 natural flavonoid compounds which is a useful tool for drug discovery as an important source of lead compounds.

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

MCE 3D Diverse Fragment Library consists of 5,196 non-flat fragment-like molecules (average Fsp3 value 0.58). More than 4,700 fragment compounds contain at least one chiral center in the structure. The key concepts that underlie the library design were 3D shape, structural diversity, reactive functionality and fragment-like. This 3D Diverse Fragment Library brings higher fragment hit optimization and increases the likelihood to find innovative hits in FBDD.

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 406 small molecules related to extracellular vesicles (EVs). It is a good tool to be used for research on metabolize, cancer and other diseases.

Obesity is widely recognized as the largest and fastest growing public health problem and is associated with numerous chronic disorders including osteoarthritis, obstructive sleep apnea, gallstones, fatty liver disease, reproductive and gastrointestinal cancers, dyslipidemia, hypertension, type 2 diabetes, heart failure, coronary artery disease, stroke, etc. Although obesity has long been associated with serious health issues, it has only recently been regarded as a disease in the sense of being a specific target for medical therapy. Obesity may be viewed as the dysregulation of two physiological functions, appetite regulation and energy metabolism, which combine to create disordered energy balance. Consequently, developing obesity treatments that target novel pathways is a growing focus for both biopharmaceutical industries.

MCE Anti-Obesity Compound Library owns a unique collection of 2,361 compounds, which mainly target signaling pathway of controlling appetite, fatty acid metabolism and energy expenditure, etc. This library is a useful tool for discovery anti-obesity drugs.

Pain is a kind of distressing feeling caused by the stimulation of tissue damage. According to the International Association for the Study of Pain (IASP), pain is defined as ”An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage”.

Pain is usually classified according to its location, duration, underlying causes, and intensity. For example, acute and chronic pain, muscle pain, and nerve pain. Pain is the main symptom of most diseases, which seriously affects the quality of life and body function of patients. In the medical treatment of pain, anti-inflammatory drugs and opioid analgesic agents have traditionally been used, but the side effects are serious. In recent years, targeted drugs targeting the ERK/MAPK pathway or other targets have gradually become a research hotspot.

MCE supplies a unique collection of 1,930 compounds targeting key proteins in the pain system. MCE Pain-Related Compound Library is a useful tool for pain related research and anti-pain drug development.

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 39 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.

The immune system is a host defense system comprising many biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, known as pathogens, from viruses to parasitic worms, and distinguish them from the organism's own healthy tissue. Inflammation is also the body's attempt at self-protection to remove harmful stimuli and begin the healing process. It’s part of the body's immune response. The immune system recognizes damaged cells, irritants, and pathogens, and inflammation begins the healing process. Inflammatory abnormalities are a large group of disorders that underlie a vast variety of human diseases. The immune system is often involved with inflammatory disorders, demonstrated in both allergic reactions and some myopathies, with many immune system disorders resulting in abnormal inflammation.

MCE designs a unique collection of 5,054 compounds that are useful tool for Immunology/Inflammation research or autoimmune inflammatory diseases drug discovery.

Inflammasomes are classic pattern recognition receptors for natural immune responses. Inflammasomes are polymeric protein complexes that regulate inflammatory responses and pyrolytic cell death, thereby exerting the host's defense against microorganisms. Inflammasomes sensors are associated with adapter proteins, activating inflammatory caspase-1, releasing inflammatory cytokines and inducing cell death, endowing the host with defense against pathogens. NLRP1, NLRP3, NLRC4, AIM2, and pyrin are considered typical inflammasomes because they convert cysteine asparaginase-1 into catalytically active capsaicin-1. In addition to infectious diseases, the importance of inflammasomes is also related to various clinical diseases, such as autoimmune diseases, neurodegeneration and metabolic disorders, and the development of cancer. Therefore, it is necessary to strictly regulate the activation and function of inflammasomes to avoid accidental host tissue damage while inducing pathogens to kill the inflammatory response.

MCE designs a unique collection of 68 inflammasomes related compounds. It is a good tool to be used for research on Inflammation, cancer and other diseases.

Mitochondria plays an important role in many vital processes in cells, including energy production, fatty-acid oxidation and the Tricarboxylic Acid (TCA) cycle, calcium signaling, permeability transition, apoptosis and heat production. At present, it is recognized that many diseases are associated with impaired mitochondrial function, such as increased accumulation of ROS and decreased OXPHOS and ATP production. Mitochondria are recognized as one of the most important targets for new drug design in cancer, cardiovascular, and neurological diseases, etc. Some small molecule drugs or biologics can act on mitochondria through various pathways, including ETC inhibition, OXPHOS uncoupling, mitochondrial Ca²⁺ modulation, and control of oxidative stress via decrease or increase of mitochondrial ROS accumulation.

MCE supplies a unique collection of 894 mitochondria-targeted compound that mainly targeting Mitochondrial Metabolism, ATP Synthase, Mitophagy, Reactive Oxygen Species, etc. MCE Mitochondria-Targeted Compound Library is a useful tool for mitochondria-targeted drug discovery and related research.

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 3,165 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.

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 827 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.

Most of molecules enter or leave cells mainly via membrane transport proteins, which play important roles in several cellular functions, including cell metabolism, ion homeostasis, signal transduction, the recognition process in the immune system, energy transduction, etc. There are three major types of transport proteins, ATP-powered pumps, channel proteins and transporters. Transport proteins such as channels and transporters play important roles in the maintenance of intracellular homeostasis, and mutations in these transport protein genes have been identified in the pathogenesis of a number of hereditary diseases. In the central nervous system, ion channels have been linked to, but not limited to, many diseases such asataxias, paralyses, epilepsies, and deafness. This indicates the roles of ion channels in the initiation and coordination of movement, sensory perception, and encoding and processing of information. Ion channels are a major class of drug targets in drug development.

MCE designs a unique collection of 1,404 smal-molecule modulators that can be used for the research of Ion Channel and Membrane Transporter or high throughput screening (HTS) related drug discovery.

Blood cancers, also called hematologic cancers, occur when abnormal blood cells start growing out of control, interrupting the function of normal blood cells, which fight off infection and produce new blood cells. Most blood cancers start in the bone marrow, which is where blood is produced. There are three main types of blood cancers: leukemia, lymphoma and myeloma, which afflict millions of children and adults every year, and are often deadly.

Some common blood cancer treatments include stem cell transplantation, chemotherapy, radiation therapy, targeted therapy, immunotherapy or a combination thereof. As we begin to understand the key signaling pathways and molecular drivers of malignant transformation in haematological disorders, new treatment strategies will continue to be developed.

MCE offers a unique collection of 2,706 compounds with identified and potential anti-blood cancer activity. These compounds target blood cancer’s major targets and signaling pathways. MCE anti-blood cancer compound library is a useful tool for anti-blood cancer drugs screening and other related research.

Nuclear factor-κB (NF-κB)/Rel proteins include NF-κB2 p52/p100, NF-κB1 p50/p105, c-Rel, RelA/p65, and RelB. These proteins function as dimeric transcription factors that regulate the expression of genes and influence a broad range of biological processes including innate and adaptive immunity, inflammation, stress responses, B-cell development, and lymphoid organogenesis. NF-κB plays a key role in regulating the immune response to infection. In addition, activation of the NF-κB pathway is involved in the pathogenesis of chronic inflammatory diseases, such as asthma, rheumatoid arthritis, and inflammatory bowel disease. Incorrect regulation of NF-κB has been linked to cancer, inflammatory and autoimmune diseases, septic shock, viral infection, and improper immune development.

MCE owns a unique collection of 809 small molecule compounds that can be used in the research of NF-κB signaling pathway or high throughput screening (HTS) related drug discovery.

Ion channel is a membrane-binding enzyme whose catalytic site is an ion conduction pore, which is opened and closed in response to specific environmental stimuli (voltage, ligand concentration, membrane tension, temperature, etc.). Ion channel provide pores for the passive diffusion of ions on the biofilm. Due to their high selectivity for ion, ion channel are generally classified as sodium (Na⁺ ), potassium (K⁺ ), calcium (Ca²⁺ ), chloride (Cl^- ), and non-specific cation channel. Ion channel is an important contributor to cell signal transduction and homeostasis. In addition to electrical signal transduction, ion channel also have many functions: regulating vascular smooth muscle contraction, maintaining normal cell volume, regulating glandular secretion, protein kinase activation, etc. Therefore, dysfunction of ion channel can lead to many diseases, and its mechanism research is particularly important.

MCE designs a unique collection of 1,129 small molecules related to ion channel, mainly targeting Na⁺ channel, K⁺ channel, Ca²⁺ channel, GABA receptor, iGluR, etc. It is an essential tool for research of cardiovascular diseases, Nervous system diseases and other diseases.

Small molecule covalent inhibitors, or irreversible inhibitors, are a type of inhibitors that exert their biological functions by irreversibly binding to target through covalent bonds. Compared with non-covalent inhibitors, covalent inhibitors have obvious advantages in bioactivity, such that covalent warheads can target rare residues of a particular target protein, thus leading to the development of highly selective inhibitors and achieving a more complete and continued target occupancy in living systems. In recent years, the distinct strengths of covalent inhibitors in overcoming drug resistance had been recognized. However, toxicity can be a real challenge related to this class of therapeutics due to their potential for off-target reactivity and has led to these drugs being disfavored as a drug class. The drug design and optimization of covalent inhibitors has become a hot spot in drug discovery.

MCE covalent inhibitor library contains 1,676 small molecules including identified covalent inhibitors and other bioactive molecules having common covalent reactive groups as warheads, such as acrylamides, activated terminal acetylenes, Sulfonyl fluorides/esters, cloracetamides, alkyl halides, epoxides, aziridines, disulfides, etc.

Chemokines, or chemotactic cytokines, are small cytokines or signaling proteins secreted by cells. They are a component of intercellular communication, controlling the directional movement of immune cells especially leukocytes, as well as other cell types, for instance, endothelial and epithelial cells, which are essential to maintain human health and the function of the immune system.

The biological effects of chemokines are achieved by binding to chemokine receptors, which are G protein-coupled receptors found on the surface of leukocytes. Some chemokine receptors are involved in directing tumor metastasis and over-expression by certain tumors. So inhibiting the interaction between chemokine and chemokine receptors on the surface of tumor cells may be a new possible therapeutic approach. Some chemokine receptors are coreceptors for HIV entry, and related inhibitors have been approved by the FDA to treat patients with HIV. Obviously, chemokines and chemokine receptors have become new targets for studying cancer, HIV, inflammation, and other diseases.

MCE supplies a unique collection of 149 chemokine or chemokine receptor inhibitors and activators, all of which have the identified inhibitory or activated effect on chemokine or chemokine receptors. MCE Chemokine Library is a useful tool for drug research related to cancer, AIDS, and wound therapy.

Drug-induced liver injury (DILI; also known as drug-induced hepatotoxicity) is caused by medications (prescription or OTC), herbal and dietary supplements (HDS), or other xenobiotics that result in abnormalities in liver tests or in hepatic dysfunction that cannot be explained by other causes. Drugs are an important cause of liver injury. Drug-induced hepatic injury is the most common reason cited for withdrawal of an approved drug.

DILI is thought to occur via several different mechanisms. Among these are direct impairment of the structural (e.g., mitochondrial dysfunction) and functional integrity of the liver; production of a metabolite that alters hepatocellular structure and function; production of a reactive drug metabolite that binds to hepatic proteins to produce new antigenic drug-protein adducts, which are targeted by hosts’ defenses (the hapten hypothesis); and initiation of a systemic hypersensitivity response (i.e., drug allergy) that damages the liver.

MCE Drug-induced Liver Injury (DILI) Compound Library contains a unique collection of 1,392 hepatotoxicity causing compounds and is a powerful tool to research DILI and other drug toxicities. This library can be used to understand the mechanisms of DILI, identify biomarkers for early DILI prediction, and allow timely recognition during drug development, thus finally achieving successful DILI prevention and assessment in the pre-marketing phase.