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

MCE Drug Repurposing Compound Library plus contains 5,643 approved and passed phase I clinical drugs, which have been completed extensive preclinical and clinical studies and have well-characterized bioactivities, safety and bioavailability properties.

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

19F-NMR has proved to be a detection mode in fragment-based drug discovery (FBDD) for studies of protein structure and interactions. 19F shows high sensitivity for NMR detection, and the exquisite sensitivity of 19F chemical shifts and linewidths to ligand binding all make it a valuable approach in FBDD.F (Fluorine) -Fragments can be used for 19F-NMR detection after binding to target proteins, and can be used as an effective 19F-NMR tool for FBDD.

MCE designs a unique collection of 4,971 F-fragments, 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 F-fragments library is an important source of lead-like 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 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 4,844 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.

The transforming growth factor beta (TGF-β) signaling pathway is involved in many cellular processes in both the adult organism and the developing embryo including cell growth, cell differentiation, apoptosis, cellular homeostasis and other cellular functions. The TGF-β superfamily comprises TGF-βs, bone morphogenetic proteins (BMPs), activins and related proteins. Signaling begins with the binding of a TGF beta superfamily ligand to a TGF beta type II receptor. The type II receptor is a serine/threonine receptor kinase, which catalyzes the phosphorylation of the Type I receptor. The type I receptor then phosphorylates receptor-regulated SMADs (R-SMADs) which can now bind the coSMAD (e.g. SMAD4). R-SMAD/coSMAD complexes accumulate in the nucleus where they act as transcription factors and participate in the regulation of target gene expression. Deregulation of TGF-β signaling contributes to developmental defects and human diseases, including cancers, some bone diseases, chronic kidney disease, etc.

MCE designs a unique collection of 226 TGF-beta/Smad signaling pathway compounds. TGF-beta/Smad Compound Library acts as a useful tool for TGF-beta/Smad-related drug screening and disease research.

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

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

MCE Anti-diabetic Compound Library owns a unique collection of 748 compounds, which mainly target SGLT, PPAR, DPP-4, AMPK, Dipeptidyl Peptidase, Glucagon Receptor, etc. This library is a useful tool for discovery anti-diabetes drugs.

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 129 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.

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 2,945 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.

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.

Hepatitis C virus (HCV) is a hepatotropic enveloped positive- strand RNA virus (family Flaviviridae) that infects the parenchymal cells of the liver. HCV infection is a significant public health burden. Globally, an estimated 71 million people have chronic hepatitis C virus infection. A significant number of those who are chronically infected will develop cirrhosis or liver cancer. To date, there is no vaccine against HCV, and combination pegylated alpha interferon (pIFN-) and ribavirin, the main standard-of-care treatment for HCV, is effective in only a subset of patients and is associated with a wide spectrum of toxic side effects and complications. More recently, new therapeutic approaches that target essential components of the HCV life cycle have been developed, including direct-acting antiviral (DAA) that specifically block a viral enzyme or functional protein and host-targeted agents (HTA) that block interactions between host proteins and viral components that are essential to the viral life cycle. However, the genetic diversity of HCV viruses and the stage of liver disease (i.e., cirrhosis) are revealing themselves as obstacles for effective, pan-genotypic treatments. There still exists a need for the discovery and development of new HCV inhibitors. In particular, since the future of HCV therapy will likely consist of a cocktail approach using multiple inhibitors that target different steps of infection, new antivirals targeting all steps of the viral infection cycle.

MCE offers a unique collection of 283 compounds with identified and potential anti-HCV activity. MCE Anti- Hepatitis C Virus Compound Library is a useful tool for discovery new anti-HCV drugs and other anti-infection research.

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.

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 58 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.