development

Flavors and fragrances serve as indispensable enhancing elements in modern industries, playing multidimensional roles in the fields of food, cosmetics, and pharmaceutical development. In the food industry, flavors and fragrances are not only used to compensate for flavor loss during processing but also to create novel sensory experiences and enhance product appeal. Natural flavors such as vanilla and citrus oils impart rich, layered aromas to foods, while synthetic flavors can precisely replicate specific tastes, meeting the demands of standardized production and extending the flavor stability of food products. In the cosmetics sector, flavors and fragrances are key to emotional design. They enhance product recognition and elevate the pleasure of use through pleasant scents. In pharmaceutical development, the application of flavors and fragrances focuses on improving compliance. Especially in formulations such as oral liquids and chewable tablets, the addition of mint, fruit, and other flavoring components effectively masks the bitter or irritating taste of medications, increasing patient acceptance. Additionally, some natural flavors may themselves possess auxiliary therapeutic benefits.

MCE contains 498 kinds of flavors and fragrances, which can be used in fields such as food, cosmetics and drug development.

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 2,495 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.

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 181 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 Ancient Chinese Classical Formulas, released by the State Administration of Traditional Chinese Medicine, selects the classic prescriptions from more than 100,000 prescriptions contained in more than 100 representative ancient medical books. Experts said that the classic prescription derived from ancient books, with thousands of years of human experience, is widely used in common diseases, frequented diseases, chronic diseases and other fields, and its development and utilization can fill the gap in medical drugs for some diseases in China, and effectively alleviate the increasingly severe medical needs brought by a series of social problems such as aging and chronic diseases in China. MCE has collected and sorted out these monomer compounds from the sources of ancient Chinese classical formulas, including licorice, ginseng, pinellia and other traditional Chinese medicine sources, which help to provide new ideas and new strategies for modern drug development.

MCE ancient Chinese classical formulas traditional Chinese medicine active compound library has 1,961 traditional Chinese medicine monomer compound, which can be used in the research fields of new drug development and drug target identification.

Currently,the incidence and mortality rates of clinical fungal infections remain high. Existing antifungal drugs are limited in variety and associated with numerous adverse effects, creating an urgent demand for the development of novel antifungal agents. Antifungal compound libraries can support the screening and development of new antifungal drugs.

The mechanisms of action of antifungal drugs cover key processes such as fungal cell membrane synthesis, cell wall synthesis, and cell division. They exert fungicidal or fungistatic effects by specifically targeting different molecular pathways. This library includes a variety of core analogs of antifungal drugs, making it adaptable to antifungal research in diverse scenarios. It can be used for the high-throughput screening of novel antifungal drug candidates, enabling the rapid identification of compounds with potential antifungal activity and facilitating the elucidation of drug-target interactions and resistance mechanisms. Additionally, it supports the screening of compounds and combinations that reverse drug resistance, thereby uncovering the novel antifungal potential of existing compounds.

The library comprises 8350 compounds with a well-defined screening strategy. The core sources of the compounds include analogs of known antifungal active moleculeswith a similarity score of ≥ 0.6 MCE has collected more than 500 antifungal molecules.All screened compounds conform to lead-like physicochemical properties, exhibiting both structural diversity and drug-like characteristics, and providing valuable support for the research and development of novel antifungal drugs.

Cosmetics are complex mixtures formulated through the rational blending and processing of various natural, synthetic, or extracted raw materials. The ingredients used in cosmetics are diverse in type and functionality. Based on their properties and applications, cosmetic ingredients can generally be classified into two main categories: base materials and auxiliary ingredients. The former constitutes the primary component of cosmetics, accounting for a significant proportion in formulations and serving as the key functional substances. Auxiliary ingredients, on the other hand, play roles in shaping the product, ensuring stability, or imparting color, fragrance, and other specific characteristics.Establishing a systematic ingredient database is of great significance for cosmetic research and development. By analyzing the physicochemical properties (such as oil-water partition coefficients and molecular weight distribution), biological activity mechanisms (such as antioxidant pathways and cellular signaling regulation), and compatibility of ingredients, the database can provide precise guidance for formulation design. This approach helps shorten the development cycle of cosmetic/skincare products and reduces trial-and-error costs.

MCE offers 621 types of cosmetic ingredient compounds, including antioxidants, humectants, emulsifiers, film-forming agents, and more.

Owing to the widespread transmission and frequent mutation of viral diseases, as well as the continuous emergence of new viruses and drug-resistant strains, antiviral drug development is facing increasingly stringent requirements. Antiviral compound libraries serve as important tools for drug screening, mechanism research and development, enabling the discovery and investigation of various antiviral drugs.

These compounds act through diverse antiviral mechanisms, targeting key steps in viral replication, assembly and invasion. They exert antiviral effects by inhibiting viral nucleic acid synthesis, blocking viral protein processing, and preventing viral binding to host cells. This library covers various types of antiviral compounds, including nucleosides, non-nucleosides, protease inhibitors and integrase inhibitors. It supports research on influenza virus, herpes virus, hepatitis virus, emerging respiratory viruses and other pathogens, and enables high-throughput screening of novel antiviral candidates to rapidly identify potential active compounds against diverse viruses. It also facilitates mechanistic studies to elucidate drug-target interactions and viral resistance mechanisms, and supports the screening of effective compounds against mutant strains for research on viral variation and drug resistance.

This antiviral library consists of 6,804 compounds with lead-like physicochemical properties. The core sources of the compounds include analogs of known antiviral molecues with a similarity score ≥ 0.6. MCE has collected more than 1450 antiviral molecules. As a small-molecule collection with both activity potential and structural modifiability, it provides strong support for antiviral drug research and 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 3,844 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.

CRBN, namely cereblon, is the substrate recognition subunit of the E3 ubiquitin ligase complex in the ubiquitin-proteasome system. A CRBN ligand library refers to a collection of numerous fragments that can specifically bind to the CRBN protein.

These ligands are mostly designed based on validated CRBN-binding warheads and modified through AI-driven molecular generation optimization systems. They not only include classic lenalidomide-derived structures but also cover novel non-lenalidomide scaffolds. After drug-likeness filtering, these ligands exhibit structural diversity and favorable druggable properties. They can be further optimized and modified to facilitate the development of novel molecular glue degraders, accelerate the discovery of molecular glues that induce interactions between CRBN and new substrate proteins, and enable the exploration of novel CRBN substrates for identifying previously unknown CRBN-binding proteins.

MCE compiles 118 fragments that can specifically bind to the CRBN protein, with molecular weights ranging from 200 to 500. Compounds developed based on the library ligands target multiple disease targets such as cancer and autoimmune diseases, further advancing the development of Molecular Glues and PROTACs therapeutic agents.

From target identification to clinical research, traditional drug discovery and development is a time-consuming and costly process, which also bears high risk. Compared with traditional drug discovery, drug repositioning or repurposing, also known as old drugs for new uses can greatly shorten the development cycle and reduce development cost, which has become a new trend of drug development. After undergoing clinical trials, approved drugs have identified bioactivities, good pharmacokinetic characteristics and safety, which can greatly improve the success rate of drug discovery. A number of successes have been achieved, such as metformin for type 2 diabetes and thalidomide for leprosy and multiple myeloma, etc.

MCE provides a unique collection of 1,495 China NMPA (National Medical Products Administration) approved compounds, which have undergone extensive preclinical and clinical studies and have well-characterized bioactivities, safety and bioavailability properties. MCE NMPA-Approved Drug Library is a good tool for drug repurposing which could dramatically accelerate drug development.

Sulfonyl fluoride (-SO₂F) overcomes the bottleneck of target selectivity in traditional covalent warheads through its unique chemical and biological properties, which rely heavily on cysteine (Cys) residues. Featuring high stability and tunable electrophilicity under physiological conditions, it can target a wide range of nucleophilic residues including lysine (Lys), tyrosine (Tyr), serine (Ser), and histidine (His). It offers the advantages of a broader druggable space, lower off-target risks, and long-lasting efficacy, with numerous reported cases in the research of covalent inhibitors, Molecular glue, PROTACs, and chemical biology probe development.

MCE constructs a highly diverse sulfonyl fluoride fragment library based on the reactivity, stability and physiological compatibility of sulfonyl fluoride. The library contains 1000 efficiently synthesized and stable sulfonyl fluoride fragments, which ensure precise reactivity of the warhead and retain sufficient derivatization space for subsequent optimization. Combined with the modular strategy of SuFEx click chemistry, it enables versatile modification of compounds and functionalization of complex molecules, improves the efficiency of structural optimization and rapidly expands druggability, making it suitable for high-throughput probe and custom covalent library construction. It provides an efficient research tool for the development of broad-spectrum covalent inhibitors targeting Lys/Tyr/Ser/His, covalent PROTACs for E3 ligases and chemical biology probe development, meeting the requirements of modern drug research for high throughput, high success rate and high derivatization potential.

This library contains 1,162 sulfonyl fluoride fragments with high structural diversity, favorable drug-like properties and tunable electrophilicity. It is well suited for precise targeting of non-Cys residues and meets the criteria of simple structure and high derivatization potential. It effectively improves

The rising prevalence of multidrug-resistant and extensively drug-resistant bacteria, combined with emerging resistance mechanisms and the limitations of existing antibacterial drugs, creates an urgent need for novel antibacterial agents. Antibacterial compound libraries serve as key tools to support antibacterial drug screening and development.

This library features structurally diverse compounds, including small-molecule scaffolds and natural product derivatives, and exhibits diverse antibacterial mechanisms of action. For example, these compounds exert antibacterial effects by disrupting bacterial cell structures, interfering with bacterial metabolic processes, and inhibiting nucleic acid synthesis. The derivation of scaffold structures enhances their activity against drug-resistant bacteria and their selectivity against different types of bacteria. This library can be used for the high-throughput screening of novel antibacterial drug candidates and the identification of potent compounds against drug-resistant and multidrug-resistant bacteria. Additionally, it provides a reference for compound structural modification, enabling further in-depth research on the structure-activity relationships(SARs) of antibacterial drugs. It can also be applied to the exploration of bacterial resistance mechanisms and reversal strategies, as well as the discovery of antibacterial molecules that inhibit efflux pumps and restore drug susceptibility.

The library contains 10855 structurally diverse drug-like compounds. Its core compound sources include analogs of known antifungal active moleculeswith a similarity score of ≥ 0.6. MCE has collected more than 1900 antibacterial molecules. All screened compounds conform to lead-like physicochemical properties, providing valuable support for the research and development of novel antibacterial drugs.

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

MCE owns a unique collection of 3,211 approved compounds which have been completed extensive preclinical and clinical studies and have well-characterized bioactivities, safety and bioavailability properties. MCE FDA-Approved Drug Library is a good tool for drug repurposing which could dramatically accelerate drug development.

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

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

Neuropeptides are small proteins produced and released by neurons through the regulation of secretory pathways, expressed in neurons and have transmitter or co-transmitter functions, and are used as nerve substrates. Neuropeptides are by far the largest and most diverse signaling molecules in the brain and have been implicated in the development of diseases and drugs. Neuropeptides are involved in inflammatory and immune diseases and have an impact on epithelial, vascular, and connective tissue cells proliferation and tissue repair. Studies have shown that neuropeptides are particularly important when the nervous system is challenged, such as stress, injury, or substance abuse. Substance P is a neuropeptide that acts as a neurotransmitter and neuromodulator in the central nervous system and is currently in clinical research and has been shown to be involved in inflammatory processes and pain.

MCE can provide 125 neuropeptides that can be used for scientific research.

A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the formation of new protein products. Proteases play important roles in regulating multiple biological processes in all living organisms, such as regulating the fate, localization, and activity of many proteins, modulating protein-protein interactions, creating new bioactive molecules, contributing to the processing of cellular information, and generating, transducing, and amplifying molecular signals.

Proteases are important targets in drug discovery. Some protease inhibitors are often used as anti-virus drugs and anti-cancer drugs. MCE offers a unique collection of 914 protease inhibitors. MCE Protease Inhibitor Library is critical for drug discovery and development.

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

MCE owns a unique collection of 3,716 compounds from approved institutions such as FDA, EMA, NMPA, PMDA, etc. or pharmacopoeia such as USP, BP, JP, etc. These compounds have well-characterized bioactivities, safety and bioavailability properties. MCE FDA Approved & Pharmacopeial Drug Library is a good tool for drug repurposing which could dramatically accelerate drug development.

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 990 compounds with identified and potential mitochondrial protective activity. MCE Mitochondrial Protection Compound Library is critical for drug discovery and 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 94 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.

With the progress of modern cancer therapy, the life of cancer patients has been extended. However, after initial treatment and recovery, the development of secondary tumors often leads to cancer recurrence. Cancer stem cells are a small number of cells that tumor growth and reproduction depend on.

Cancer stem cells have strong self-renewal ability, which is the direct cause of tumor occurrence. In addition, cancer stem cells also have the ability to differentiate into different cell types, playing a crucial role in tumor metastasis and development. Chemotherapy and radiotherapy induced DNA damage and apoptosis are common cancer treatments. However, cancer stem cells can effectively protect cancer cells from apoptosis by activating DNA repair ability. Cancer stem cells are regarded as the key "seed" of tumor occurrence, development, metastasis and recurrence. Since its first discovery in leukemia in 1994, cancer stem cells have been considered a promising therapeutic target for cancer treatment.

MCE supplies a unique collection of 3,315 compounds targeting key proteins in cancer stem cells. MCE Cancer Stem Cells Compound Library is a useful tool for cancer stem cells 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 5,478 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.

The majority of hypertensive patients have primary (or essential) hypertension, that is, hypertension in which secondary causes are not present. Management aims to control arterial pressure, prevent end-organ damage (cerebrovascular, cardiovascular, and renal), and reduce the risk of premature death.

Antihypertensive drugs may be divided into two broad groups, the first group being those which directly or indirectly block the renin–angiotensin system (RAS), for example, ACEIs, angiotensin receptor antagonists (ARAs), direct renin inhibitors (DRIs), and to a lesser extent β-blockers. The second group of drugs works by increasing water and sodium excretion, thereby reducing intravascular volume, or by causing vasodilatation through non-RAS pathways, for example, diuretics and calcium channel blockers (CCBs).

MCE offers a unique collection of 880 compounds with identified and potential antihypertensive activity. MCE Antihypertensive Compound Library is critical for antihypertensive drug discovery and 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.

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 164 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.

Heterocyclic compounds are cyclic organic compounds which contain at least one hetero atom, the most common heteroatoms are nitrogen, oxygen ,and sulfur. Heterocycles are common in biology, featuring a wide range of structures from enzyme co-factors to amino acids and proteins. On the one hand, heterocycles are common structural units in approved drugs and in medicinal chemistry targets in the drug discovery process. In addition, heterocycles have been found as a key structure in medical chemistry and also they are frequently found in large percent of biomolecules such as vitamins, natural products ,and biologically active compounds including antifungal, anti-inflammatory, antibacterial, antioxidant, antiallergic, anti-HIV, antidiabetic, anticancer activity.

MCE offers a unique collection of 6,445 heterocyclic compounds which can be used for drug discovery for high throughput screening (HTS) and high content screening (HCS). MCE heterocyclic compound library is critical for drug discovery and development.

GPCRs are a large family of cell surface receptors that respond to a variety of external signals. Binding of a signaling molecule to a GPCR results in G protein activation, which in turn triggers the production of any number of second messengers. GPCRs play an important role in the human body, and increased understanding of these receptors has greatly affected modern medicine. In fact, researchers estimate that between one-third to one-half of all approved drugs act by binding to GPCRs. GPCRs are a large group of drug targets in drug discovery.

MCE provides a unique collection of 3,350 small molecules targeting GPCRs that can be used in the screening for various GPCRs-related research and drug development projects.

Rare diseases are an important public-health issue and a challenge for the medical community. Most rare diseases are genetic disorders, which are often severely disabling, substantially affect life expectancy, and impair physical and mental abilities. Currently, there are about 7,000 identified rare diseases, together affecting 10% of the population. However, fewer than 6% of all rare diseases have an approved treatment option, highlighting their tremendous unmet needs in drug development. The process of repurposing drugs for new indications, compared with the development of novel orphan drugs, is a time-saving and cost-efficient method resulting in higher success rates, which can therefore drastically reduce the risk of drug development for rare diseases.

MCE carefully collects a unique of 1,875 compounds studied in preclinical, clinical trials or approved used in rare diseases treatment. MCE rare diseases drug library is a useful tool for the research of rare diseases. All compounds can provide corresponding indications for rare diseases.

The occurrence of diseases is often associated with multiple targets and pathways, and the factors of disease formation are complex and diverse, so the development of more powerful drugs is needed. According to statistics, 21% of the FDA-approved drugs in 2015-2017 were multi-target compounds. Multi-target compounds refer to a drug targeting multiple disease-related targets or multiple subtypes of a target. Multi-target compounds can be applied to drug screening or targeted ligand design. Because the targets of such compounds are diverse and clear, they have the characteristics of saving time and drug cost during the mechanism research of new drug research and development. In addition, due to the diversity of drug targets, multiple strategies can be applied to pharmacological studies.

MCE supplies a unique collection of 6,666 multi-target compounds that targets two or more different targets or different subtypes of the same target. MCE Multi-Target Compound Library can be used for target protein ligand screening or drug development.

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

MCE owns a unique collection of 2,510 clinical compounds that refer to various research areas including anti-cancer, anti-infection, anti-inflammation, nervous disease. Those compounds are of detailed information on clinical development status, research area, targets, etc.

Cysteine proteases (CPs), a key enzyme family regulating physiological metabolism and mediating pathological processes (e.g., abnormal bone resorption, tumour invasion, and pathogen infection), represent a core therapeutic target for disease intervention via the development of specific inhibitors. Currently reported CP covalent inhibitors encompass diverse structural types, including epoxides, aziridine, and activated double bonds (vinyl sulphones, α,β-unsaturated ketones), providing clear structural references for the development of novel CP covalent inhibitors.

This compound library contains multiple warheads that specifically target cysteine proteases, serving as a powerful tool for the efficient discovery of novel covalent inhibitors against this enzyme family.

Oceans cover more than 70% of the Earth’s surface and host a huge species diversity. Marine organisms are considered the most recent source of bioactive natural products after terrestrial plants and nonmarine microorganisms. Marine biological sources are taxonomically diverse and include sponges, tunicates, corals, mollusks, fungi, and sediment-derived bacteria.

Marine organisms can produce a plethora of small molecules with novel chemical structures and potent biological properties, being a rich source for the discovery of pharmacologically active compounds, already with several marine-derived agents approved as drugs. Ziconotide, a peptide originally discovered in a tropical cone snail, was the first marine-derived compound to be approved in the United States in December 2004 for the treatment of pain. Then, in October 2007, Trabectedin became the first marine anticancer drug to be approved in the European Union.

MCE offers a unique collection of 61 marine-sourced natural products which can be used for drug discovery for high throughput screening (HTS) and high content screening (HCS). MCE marine-sourced natural product library is an important source for drug discovery and development.

Techniques for reprogramming somatic cells create new opportunities for drug screening, disease modeling, artificial organ development, and cell therapy. The development of reprogramming techniques has grown exponentially since Yamanaka reprogrammed somatic cells to become induced pluripotent stem cells (iPSCs) using four transcription factors, OCT4, SOX2, KLF4, and c-MYC in 2006. Despite the development of efficient reprogramming methods, most methods are inappropriate for clinical applications because they carry the risk of integrating exogenous genetic factors or use oncogenes. Alternative approaches, such as those based on miRNA, non-viral genes, non-integrative vectors, and small molecules, have been studied as possible solutions to the problems. Among these alternatives, small molecules are attractive options for clinical applications. Reprogramming using small molecules is inexpensive and easy to control in a concentration- and time-dependent manner. It offers a high level of cell permeability, ease of synthesis and standardization, and it is appropriate for mass-producing cells.

MCE Reprogramming Compound Library contains a unique collection of 3,050 compounds that act on reprogramming signaling pathways. These compounds are potential stimulators for reprogramming. This library is a useful tool for researching reprogramming and regenerative medicine.

Fatty acids (FAs) are the main components of lipids. The synthesis of fatty acids mainly involves the Triglyceride (TG) cycle and De Novo Lipogenesis (DNL). Fatty acids which exist widely in organisms are components of cell membranes and play an indispensable role in cell signaling. In addition, FFAs can be taken up from circulating plasma by all mitochondria-containing cells, and they are metabolized by β-oxidation and the citric acid cycle to release large amounts of energy in the form of ATP. Abnormal fatty acid metabolism is associated with the occurrence and development of cardiovascular diseases, diabetes, fatty liver, hyperthyroidism, and other diseases.

MCE offers a unique collection of fatty acid compounds. Fatty Acids Compound Library is an important tool for the study of energy metabolism and drug development of metabolism-related diseases.

Polysaccharides are long chains of carbohydrate molecules, consisting of multiple smaller monosaccharides. Polysaccharides are found mainly in natural sources such as plants, microorganisms, algae and animals. Polysaccharides have a large number of active functional groups, different chemical compositions and different molecular weight ranges, which determines their diversity in nature and structure. Also in the field of medical research, polysaccharides act as a class of functional compounds and thus play a role. For example, nanocarrier construction, immunomodulation and vaccine development, new strategies for antitumor therapy, tissue regeneration engineering applications and disease diagnosis. With the advancement of glycomics and synthetic biotechnology, human beings are moving from “knowing polysaccharides” to “designing polysaccharides”, which will provide innovative solutions for materials science, precision medicine and sustainable development.

MCE offers 67 polysaccharides that can be used in biomedical studies.

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

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

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

MCE Drug Repurposing Compound Library contains 5,080 approved drugs and passed phase Ⅰclinical drugs, which have been completed extensive preclinical and clinical studies and have well-characterized bioactivities, safety and bioavailability properties.

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

MCE owns a unique collection of 3,211 approved compounds which have been completed extensive preclinical and clinical studies and have well-characterized bioactivities, safety and bioavailability properties. The package of this library is 96-well microplate with peelable foil seal, which makes the screening process easier and faster.

Amino acids, as one of the most fundamental organic compounds in living organisms, serve not only as the basic building blocks of proteins but also but also undertake the functions of energy supply, neurotransmitter synthesis, and maintenance of internal environment stability.Amino acid metabolic enzymes are a class of enzymes involved in the metabolic processes of amino acids, catalyzing their synthesis, breakdown, transformation, and interactions with other metabolic pathways. Abnormalities in amino acid metabolic enzymes can lead to various metabolic diseases, such as phenylketonuria and hyperammonemia, etc. Therefore, actively exploring and regulating the processes of amino acid metabolism is crucial for the development of drugs related to these diseases.

MCE designs a unique collection of 324 small molecules target amino acid metabolizing enzymes, which is an important tool for studying studying amino acid metabolism processes or metabolism-related drug development.

COVID-19 poses a serious threat to people's health, and it is urgent to develop drugs to treat COVID-19 quickly. The screening of anti-COVID-19 drugs by using the clinical and approved compounds can greatly shorten the research and development cycle. In addition, the virtual screening technology can effectively narrow the scope of screening and improve the screening efficiency in the pre-screening of new drugs.

Taking advantage of our virtual screening, we conduct virtual screening of approved compound library and clinical compound library based on the 3CL protease (PDB ID: 6LU7), Spike Glycoprotein (PDB ID: 6VSB), NSP15 (PDB ID: 6VWW), RDRP, PLPro and ACE2 (Angiotensin Converting Enzyme 2) structure. We design a unique collection of 1,383 compounds which may have anti-COVID-19 activity. Anti-COVID-19 Compound Library will be a powerful tool for screening new anti-COVID-19 activity drugs.

Protein protein interactions (PPI) have pivotal roles in life processes. The studies showed that aberrant PPI are associated with various diseases, including cancer, infectious diseases, and neurodegenerative diseases. The classic drug targets are usually enzymes, ion channels, or receptors, the PPI indicate new potential therapeutic targets. Therefore, targeting PPI is a new direction in treating diseases and an essential strategy for the development of new drugs.

However, the design of modulators targeting PPI still faces tremendous challenges, such the difficult PPI interfaces for the drug design, lack of ligands reference, lack of guidance rules for the PPI modulators development and high-resolution PPI proteins structures.

With the development of high-throughput technology, high-throughput screening is also gradually used for the identification of PPI inhibitors, but the compound library used for conventional target screening is not very effective in screening PPI inhibitors. To improve screening efficiency, MCE carefully selected 767 PPI inhibitors and mainly targeting MDM2-p53, Keap1-Nrf2, PD-1/PD-L1, Myc-Max, etc. MCE Protein-protein Interaction Inhibitor Library is a useful tool for PPI drug discovery and related research.

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

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

In drug discovery and development (R&D) area, target binding and druggability optimization are core processes. Among these attributes, high solubility is critical for a compound to achieve druggability, as it directly impacts the progress of drug R&D. Superior solubility ensures the rapid dissolution and uniform distribution of drug molecules in vivo, thereby enhancing bioavailability and effectively mitigating issues such as suboptimal efficacy, increased dosage requirements, or exacerbated toxic and side effects arising from insufficient solubility.

From the perspective of medicinal chemistry, high-solubility drug fragments serve as high-quality "molecular building blocks". Based on these fragments, lead compounds with potential druggability can be rapidly screened out, which significantly shortens the drug R&D cycle and reduces R&D costs. Meanwhile, the high-solubility drug fragment library can provide diverse options for drug development in different therapeutic areas, offer solutions for the solubility defects of existing clinical drugs, and facilitate the development of novel, highly effective targeted drugs with higher bioavailability and better safety profiles.

MCE has collected and compiled 2,527 experimentally validated small-molecule fragments with high solubility. These fragments can be directly used for drug molecular design, providing high-quality pre-validated solubility fragments that significantly improve the efficiency of lead compound screening and accelerate the progress of drug R&D.

The RNA-targeted bioactive compound library is a high-quality collection of small molecules specifically designed and curated to target RNA structures and functions. It is widely applied in cutting-edge drug discovery and life science research. Unlike traditional strategies that focus on protein targets, RNA-targeted compounds can directly modulate various functional RNA molecules by influencing their splicing, translation, stability, or structural conformation, thereby enabling precise intervention in key biological processes. In the field of drug development, these compounds provide a novel approach to addressing previously “undruggable” targets and have demonstrated significant potential in areas such as oncology, antiviral therapies, and neurodegenerative diseases. For example, by targeting disease-associated RNA structural domains or regulating the aberrant expression of non-coding RNAs, these compounds can effectively inhibit disease progression or restore normal cellular function. In mechanistic studies, RNA-targeted compounds serve as valuable chemical biology tools to elucidate the roles of RNA in gene expression regulation, cellular signaling pathways, and disease development.

The MCE RNA-targeted bioactive compound library contains 854 compounds, sourced from databases such as TargetRX Atlas and R-BIND. The library features excellent structural diversity and biological activity, making it suitable for high-throughput screening (HTS), target validation, phenotypic screening, and lead compound discovery. It represents a valuable resource for RNA-related research and innovative drug development.

MCE EMA-Approved Drug Library consists of 721 EMA-approved drugs with high pharmacological diversity. All drugs in this library have been completed extensive preclinical and clinical studies and have well-characterized bioactivities, safety and bioavailability properties. MCE EMA-Approved Drug Library is a useful tool for drug repurposing which could dramatically accelerate drug development.

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

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

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

Cell proliferation, the increase in cell numbers resulting from cell division, is a complex and tightly regulated process. Cell proliferation is regulated by coordinated entry into the cell cycle, and changes in proliferation are closely linked to disease development. Evolutionary dynamics links tumor growth and progression with cell proliferation, cell death, and mutation rates. In addition, cell proliferation is central to degenerative diseases, the development of which is often accompanied by accelerated multiplication of cancer cells. Therefore, assays of cell proliferation levels are frequently used for laboratory research purposes and increasingly for clinical assessment of tumor aggressiveness and potentially to guide care. It has been shown that multiple key targets are collectively involved in regulating the process of cell proliferation, such as CDK, E2F, pRB, β-Catenin, and others.

MCE collects 3,367 compounds that target and regulate key targets of cell proliferation, which can be used in studies of cell proliferation mechanisms and drug discovery.

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

MCE designs a unique collection of 3,603 cell death compounds, covering multiple targets, such as Apoptosis, Ferroptosis, Pyroptosis, Necroptosis, etc. It is a useful tool for screening cell death drugs.

Cell death is a core biological process that maintains homeostasis in multicellular organisms, playing a dual role in life activities. On one hand, cell death participates in physiological processes such as cell renewal and damage repair through precise regulation; on the other hand, it actively eliminates damaged, infected, or cancerous cells, thereby blocking pathological progression and preserving organism health. Cell death not only ensures the normal development and growth regulation of organisms but is also closely associated with the occurrence and development of various diseases. Numerous studies have shown that specific types of programmed cell death play critical roles in disease progression, providing an important theoretical basis for developing novel therapeutic strategies by regulating cell death pathways.

MCE offers 22 types of commonly used cell death inhibitors, such as apoptosis, ferroptosis, pyroptosis, and cuproptosis, suitable for use as positive controls in the study of novel cell death mechanisms.

Diarrhea is a disease symptom, and the pathophysiologic basis of diarrhea is a disturbance in intestinal water and electrolyte balance, which may be due to increased secretion of osmotically active electrolytes (secretory diarrhea) or increased intake of osmotically active substances (osmotic diarrhea). Food poisoning, pathogenic bacterial infections, and intestinal-related diseases can all contribute to the development of diarrhea. Traditional Chinese Medicine (TCM) considers diarrhea to be a symptom of an imbalance in the body's systems, particularly related to the functions of the spleen and stomach. Spleen qi deficiency, dampness-heat, liver and spleen disharmony are closely related to diarrhea. Many types of Chinese herbs regulate the function of diarrhea, such as: Dysosmae Verspiellis Rhixoma Et Radix, Ginkgo Semen, Forsythiae Fructus, and Campsis Flos.

MCE can provide 2,434 active monomers that can be obtained from TCM herbs with diarrhea-regulating functions, which can be applied to drug development and disease mechanism research.

MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. In mammalian cells, four MAPK families have been clearly characterized: ERK1/2, C-Jun N-terminal kinse/stress-activated protein kinase (JNK/SAPK) , p38 kinase and ERK5. They respond to different signals. Each MAPK-related cascade consists of three enzymes that are activated in series: a MAPK kinase kinase (MAPKKK), a MAPK kinase (MAPKK) and a MAP kinase (MAPK). MAPK signaling pathways has been implicated in the development of many human diseases including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS) and various types of cancers.

MCE designs a unique collection of 1,055 MAPK signaling pathway inhibitors that act as a useful tool for MAPK-related drug screening and disease research.

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 72 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.