Compound

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 1,618 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.

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 187 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.

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.

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 128 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.

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

The payload or cytotoxic agent is the most important unit in the ADC. ADC has the capability to kill cancer cell depending on the potency of the payload. MCE provides 116 highly potent cytotoxins that contain auristatin derivatives, maytansinoids, calicheamicin, duocarmycin, pyrrolobenzodiazepines (PBDs), etc.

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

MCE offers a unique collection of 712 Pediatric medicines, all of which have been approved or studied in clinical trials for children diseases. MCE children’s drug library is a useful tool for drug repurposing to discover new children’s indications.

Unlike highly conserved orthosteric sites, allosteric sites exhibit low conservation, high hydrophobicity, weak polarity, confined geometry, and dynamic cryptic properties. Rather than rigid keyhole-like cavities, they typically appear as flexible grooves, subunit interface clefts, or shallow depressions formed by protein conformational changes.

Based on the dynamic, hydrophobic, and elongated nature of allosteric pockets, MCE has carried out targeted fragment modification and screening under strict physicochemical criteria: MW 120–280 Da, HBD ≤ 2, HBA ≤ 3, PSA 30–80 Ų, rotatable bonds ≤ 2, cLogP 1–3.5. High 3D diversity was further ensured by PMI analysis, yielding fragments with excellent shape complementarity to allosteric pockets.

This library contains 1,800 structurally diverse, drug-like fragments, this library supports allosteric drug development and pocket optimization. It significantly improves screening hit rates and enables efficient, precise early-stage R&D of allosteric drugs.

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

MCE provides a unique collection of 282 chemical probes with high potency (at least 100 nM potency), selectivity (at least 10-fold selectivity against any other target) and cell-permeability (at least 10 μM potency). MCE Chemical probe library is a useful tool for target identification and mechanism research.

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

MCE supplies 450 approved food additives which are safe substances and can be used for drug discovery and other research.

Natural product have great diversity and structural complexity of scaffolds. And the number of their drugs represents a large number of sources of new pharmacological entities, so natural products are of great significance in drug discovery. The Dictionary of Natural Products (DNP) shows that natural products mainly come from plants, animals and microorganisms, and animal sources are the second important source of natural products. Animal derived natural products exist to varying degrees in almost all forms of animals, generally secondary metabolite extracted from organisms.

MCE provides a unique collection of 988 animal-sourced natural products. MCE Animal-Sourced Natural Product Library is a useful tool for drug discovery that can be used for high throughput screening (HTS) and high content screening (HCS).

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 178 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.

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 3,728 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.

Natural products are characterized by enormous scaffold diversity and structural complexity, because of which, natural products do show a wide range of biological activities. Medicinal plants have been the major source of medicines over many centuries. About a quarter of all Food and Drug Administration (FDA) and/or the European Medical Agency (EMA) approved drugs are plant based, with well-known drugs such as Paclitaxel and Aspirin having been isolated from plants.

MCE provides a unique collection of 3,352 plant-sourced natural products. MCE Plant-Sourced Natural Product Library is a useful tool for drug discovery that can be used for high throughput screening (HTS) and high content screening (HCS).

PROTACs (Proteolysis-targeting chimeras) is a class of molecules that utilize ubiquitin-proteasome system (UPS) to ubiquitinate and degrade target proteins. The PROTACs molecule consists of two ligands joined by a linker. The one-to-one interaction between PROTACs and target proteins determines the high efficiency of PROTACs, making it a potential molecule for targeted protein degradation (TPD) therapy.

MCE supplies a unique collection of 544 PROTACs that effectively degrade target proteins with more powerful screening capability. MCE PROTAC Library is a useful tool for signal pathway research, protein degradation therapy research, drug discovery and drug repurposing, etc.

Bile acids are a class of amphiphilic molecules derived from the metabolic breakdown of cholesterol, primarily synthesized in the liver, and play a crucial role in the intestines. Based on their structural characteristics, bile acids are mainly divided into two categories: free bile acids (including Cholic acid, Deoxycholic acid, Chenodeoxycholic acid) and conjugated bile acids (including Glycocholic acid, Glycochenodeoxycholic acid, Taurocholic acid, etc.). Bile acids play a significant role in the pathophysiological research of liver and gastrointestinal diseases and are closely associated with the occurrence of metabolic diseases such as obesity, type II diabetes, non-alcoholic fatty liver disease, and atherosclerosis. Bile acids maintain metabolic balance within the body by regulating sugar metabolism, lipid metabolism, and amino acid metabolism, and they influence the activity of metabolism-related enzymes and transporters. In addition, Bile acids can also be used to construct a bile acid metabolism research platform, which helps to delve into the metabolic pathways and dynamic changes of bile acids in living organisms and aids in identifying new biomarkers for certain diseases.

MCE included 62 bile acids, including Cholic acid, Deoxycholic acid, Glycocholic acid, etc., which are effective tools for the study of liver and gallbladder diseases.

Sodium channels conduct sodium ions (Na+) through a cell's plasma membrane that are the source of excitatory currents for the nervous system and muscle. Na channels are classified according to the trigger that opens the channel for such ions, i.e. either a voltage-change (Voltage-gated, voltage-sensitive, or voltage-dependent sodium channel also called VGSCs or Nav channel) or a binding of a substance (a ligand) to the channel (ligand-gated sodium channels). Dysfunction in voltage-gated sodium channels correlates with neurological and cardiac diseases, including epilepsy, myopathies, pain and cardiac arrhythmias. Sodium channel blockers are used in the treatment of cardiac arrhythmia, pain and convulsion.

MCE offers a unique collection of 199 sodium channel blocker and antagonists, all of which have the identified inhibitory effect on sodium channels. MCE Sodium Channel Blocker Library can be used for neurological and cardiac diseases drug discovery and sodium channel research.

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

MCE carefully prepared a unique collection of 2,921 off-patent drugs, which is a good choice for drug repurposing.

MCE EMA-Approved Drug Library consists of 728 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.

Sulfonyl fluoride (-SO₂F) overcomes the poor target selectivity of traditional covalent warheads that rely heavily on cysteine. With high stability and tunable electrophilicity under physiological conditions, it targets multiple nucleophilic residues including Lys, Tyr, Ser and His, offering expanded druggable space, lower off-target risks and prolonged efficacy. It is widely used in covalent inhibitors, molecular glues, PROTACs and chemical probes.

MCE has built a highly diverse sulfonyl fluoride fragment library with 1,162 structurally diverse, drug-like fragments. Designed for balanced reactivity, stability and compatibility, these molecules feature tunable electrophilicity, simple scaffolds and high derivatization potential. Combined with SuFEx click chemistry, the library enables efficient modular modification and rapid structure optimization.

Ideal for targeting non-cysteine residues, this library improves covalent screening and probe development efficiency, serving as a precise tool for early-stage covalent drug discovery and chemical biology research.

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