L-Cystine-³⁴S₂

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 671 children’s 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.

The health benefits deriving from the consumption of certain foods have been common knowledge. All foods are made up of chemical substances. Chemicals in foods are largely harmless and often desirable. At present, numerous researchers have been focused on the beneficial role played by certain food components in the close relationship between food intake and health status. For example, polyphenols, a common class of compounds among foods, are well-known antioxidants, which may play a role in the prevention of several diseases including type 2 diabetes, cardiovascular diseases, and some types of cancer.

MCE supplies a unique collection of 1967 compounds from variety of foods. All compounds are with specific food source(s). MCE Food-Sourced Compound Library is the useful tool to discover molecules with pharmaceutical activity from foods.

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

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

Alzheimer’s Disease (AD) is a progressive degenerative brain disease which causes mental and physical decline, gradually resulting in death. Despite the significant public health issue that it poses, only few medical treatments have been approved for Alzheimer’s Disease (AD) and these act to control symptoms rather than alter the course of the disease. Discovery of new therapeutic approaches depends on the study of pathology of AD. Recent research findings have led to greater understanding of disease neurobiology in Alzheimer's Disease (AD) and identification of unique targets for drug development. Several important mechanisms have been proposed to explain the underlying pathology of AD, such as Amyloid cascade hypothesis, Tau hypothesis and Cholinergic hypothesis, etc.

MCE offers a unique collection of 1374 compounds with anti-Alzheimer’s Disease activities or targeting the unique targets of AD. MCE Anti-Alzheimer’s Disease Compound Library is a useful tool for exploring the mechanism of AD and discovering new drugs for AD.

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 856 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.

Protein ubiquitination is an enzymatic post-translational modification in which an ubiquitin protein is attached to a substrate protein. Ubiquitination involves three main steps: activation, conjugation, and ligation, performed by ubiquitin-activating enzymes (E1s), ubiquitin-conjugating enzymes (E2s), and ubiquitin ligases (E3s), respectively. Ubiquitination affects cellular processes such as apoptosis, cell cycle, DNA damage repair, and membrane transportation, etc. by regulating the degradation of proteins (via the proteasome and lysosome), altering the cellular localization of proteins, affecting proteins activity, and promoting or preventing protein-protein interactions. Deregulation of ubiquitin pathway leads to many diseases such as neurodegeneration, cancer, infection and immunity, etc.

MCE offers a unique collection of 286 small molecule modulators with biological activity used for ubiquitination research. Compounds in this library target the key enzymes in ubiquitin pathway. MCE Ubiquitination Compound Library is a useful tool for the research of ubiquitination regulation and the corresponding diseases.

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

MCE offers a unique collection of 2228 compounds with anti-Neurodegenerative Diseases activities or targeting the unique targets of neurodegenerative diseases. MCE Neurodegenerative Disease-related Compound Library is a useful tool for exploring the mechanism of neurodegenerative diseases and discovering new drugs for neurodegenerative diseases.

Parkinson’s disease (PD), the second most common age-associated neurodegenerative disorder, is characterized by the loss of dopaminergic (DA) neurons and the presence of α-synuclein-containing aggregates in the substantia nigra pars compacta (SNpc). Motor features such as tremor, rigidity, bradykinesia and postural instability are common traits of PD. To date, there is no treatment to stop or at least slow down the progression of the disease. The etiology and pathogenesis of PD is still elusive, however, a large body of evidence suggests a prominent role of oxidative stress, inflammation, apoptosis, mitochondrial dysfunction and proteasome dysfunction in the pathogenesis of PD.

MCE offers a unique collection of 1339 compounds with anti- Parkinson’s Disease activities or targeting the unique targets of PD. MCE Anti- Parkinson's Disease Compound Library is a useful tool for exploring the mechanism of PD and discovering new drugs for PD.

Neurodegenerative diseases are characterised by progressive dysfunction and death of neurons, such as Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis (MS). Neuroprotection is an approach to preserve neurons so that neurons cannot be hurt by different pathological factors in neurodegenerative diseases. Neuroprotectors are some agonists and antagonists targeting some key targets in neuroprotactive signal pathways, such as calcium and sodium channel blockers, GABA receptor agonists, NMDA receptor Antagonists, etc. Current neuroprotectors cannot reverse existing damage, but they may protect against further nerve damage and slow down any degeneration of the central nervous system (CNS) and still play important roles in the treatment of neurodegenerative diseases.

MCE offers a unique collection of 1058 compounds with potential neuroprotective activities. These compounds mainly act on some key targets in neuroprotetive signal pathways, such as calcium channel, sodium channel, adenosine A1 receptor, etc. MCE Neuroprotective Compopund Library is a useful tool in neuroprotective drug discovery.

An infection occurs when another organism enters a person’s body and causes disease. The organisms that cause infections are very diverse and can include things like viruses, bacteria, fungi, and parasites. The immune system is an effective barrier against infectious agents.

MCE provides a unique collection of 2882 anti-infective compounds with anti-bacterial, anti-viral, anti-fungal and anti-parasite activities that can be used for drug screening and other research in anti-microbial area.

MCE 5K Scaffold Library consists of 5,000 lead-like compounds. Each compound represents one unique scaffold. All compounds are compatible with Lipinski’s rule (Rule of 5) with multiple characteristics such as calculated good solubility (-3.2<logP<5), oral bioavailability (RotB<=10), drug transportability (PSA<120). Compounds contained within the library have been screened to remove any inappropriate chemical structures, avoiding “false hits”. The sufficient diverse of compound structure makes this library a powerful tool for drug screening.

Glucose homeostasis is tightly regulated to meet the energy requirements of the vital organs and maintain an individual’s health. Glucose metabolism includes glycolysis, tricarboxylic acid cycle, pentose phosphate pathway, oxidative phosphorylation and other metabolic pathways. Glucose is the major carbon source that provides the main energy for life. Glucose metabolism dysregulation is also implicated in many diseases such as diabetes, heart disease, neurodegenerative diseases and even cancer.

MCE offers a unique collection of 1001 compounds related to glucose metabolism, which target glucose metabolism related targets, such as GLUT, Hexokinase, Pyruvate Kinase, IDH, etc. MCE glucose metabolism library is a powerful tool for studying glucose metabolism and drug discovery of diseases related to glucose metabolism.

Cancer is one of the leading causes of mortality amongst world’s population, in which prostate cancer (PCa) is one of the most encountered malignancies among men. Several molecular mechanisms are involved in prostate cancer development and progression. These include common survival factors in prostate cancer (IGF-1), growth factors (TGF-α, EGF), Wnt, Hedgehog, NF-κB, and mTOR and other signaling pathways. These provide potential therapeutic target in prostate cancer treatment.

MCE offers a unique collection of 2295 compounds with identified and potential anti-prostate cancer activity. MCE Anti-Prostate Cancer Compound Library is a useful tool for anti-prostate cancer drugs screening and other related research.

Nuclear receptors (NR) are proteins found in cells that sense androgen and thyroid hormones and certain other molecules. They are ligand-activated transcription factors that participate in many aspects of human physiology and pathology, and regulate the expression of various important genes.

Nuclear receptors have become one of the main targets in the development of new drug strategies, providing a unique type of receptors for studying a variety of human diseases, such as breast cancers, skin disorders and diabetes. 13% of U.S. Food and Drug Administration (FDA) approved drugs target nuclear receptors.

MCE supplies a unique collection of 661 nuclear receptor inhibitors and activators, all of which have the identified inhibitory or activated effect on nuclear receptor. MCE Nuclear Receptor Library is a useful tool for drugs research related to cancer, skin disease and diabetes.

MCE 50K Diversity Library consists of 50,000 lead-like compounds with multiple characteristics such as calculated good solubility (-3.2<logP<5), oral bioavailability (RotB<=10), drug transportability (PSA<120). These compounds were selected by dissimilarity search with an average Tanimoto Coefficient of 0.52. There are 36,857 unique scaffolds and each scaffold 1 to 7 compounds. What’s more, compounds with the same scaffold have as many functional groups as possible, which make abundant chemical spaces. This exceptionally diverse library is highly recommended for random screening against new as well as popular targets based its novel, diverse scaffolds, abundant chemical spaces and the convenience for subsequent modification.

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 5006 compounds that are useful tool for Immunology/Inflammation research or autoimmune inflammatory diseases drug discovery.

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 511 natural flavonoid compounds which is a useful tool for drug discovery as an important source of lead compounds.

Immuno-Oncology is a type of immunotherapy that has the specific purpose of treating cancer. It works by stimulating our immune system to fight back. Normally, our immune system is able to destroy cancer cells in our body, however sometimes cancer cells can adapt and mutate, effectively hiding from our immune system. This is when tumors can develop and become a threat to our health. Immuno-oncology involves mobilizing lymphocytes to recognize and eliminate cancer cells using the body’s immune system. There are several immuno-oncology treatments available, including Immune cell therapy (CAR-T), monoclonal antibodies (mABs) and checkpoint inhibitors, cytokines and cancer vaccines.

MCE Small Molecule Immuno-Oncology Compound Library offers 486 bioactive tumor immunology compounds that target some important checkpoints such as PD1/PD-L1, CXCR, Sting, IDO, TLR, etc. This library is a useful tool for Immuno-oncology research.

Natural products are small molecules produced naturally by any organism including primary and secondary metabolites. Natural sources may lead to basic research on potential bioactive components for commercial development as lead compounds in drug discovery.

Nature has been a source of medicinal agents for thousands of years, and an impressive number of modern drugs have been isolated from natural sources, many based on their use in traditional medicine. With the development of new molecular targets, there is an increasing demand for novel molecular diversity for screening. Natural products will play a crucial role in meeting this demand through the continued investigation of world’s bio-diversity, much of which remains unexplored.

MCE provides a unique collection of 4531 natural compounds that contain Saccharides and Glycosides, Phenylpropanoids, Quinones, Flavonoids, Terpenoids and Glycosides, Steroids, Alkaloid, Phenols, Acids and Aldehydes. Natural Product Library is a useful tool for drug discovery that can be used for high throughput screening (HTS) and high content screening (HCS).

Viruses are much simpler organisms than bacteria, and they are made from protein substances and nucleic acid. Despite the fact that the exact mechanism of infection is extremely specific to each type of virus, the general scheme of infection can be represented in the following manner: A virus is absorbed at the surface of a host cell and then permeates through the membrane, where it releases nucleic acid from its protein protection. Then the viral nucleic acid begins to replicate, and transcription of the viral genome takes place either in the cytoplasm, or in the nucleus of the host cell. As a result of these events, a large amount of viral nucleic acid and protein are made to make new generations of virions. Therefore, one mechanism of action of antiviral drugs is to interfere with the ability of a virus to get into a target cell. A second mechanism of action is to target the processes that synthesize virus components after a virus invades a cell, such as nucleotide or nucleoside analogs.

MCE designs a unique collection of 1270 anti-virus compounds that target several viruses, including SARS-CoV, HBV, HCV, HIV, HSV and Influenza Virus. It’s an effective tool for anti-virus 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 2676 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.

Natural products are small molecules produced naturally by any organism including primary and secondary metabolites. Natural sources may lead to basic research on potential bioactive components for commercial development as lead compounds in drug discovery.

Nature has been a source of medicinal agents for thousands of years, and an impressive number of modern drugs have been isolated from natural sources, many based on their use in traditional medicine. With the development of new molecular targets, there is an increasing demand for novel molecular diversity for screening. Natural products will play a crucial role in meeting this demand through the continued investigation of world’s bio-diversity, much of which remains unexplored.

MCE provides a unique collection of 5315 natural compounds that contains Saccharides and Glycosides, Phenylpropanoids, Quinones, Flavonoids, Terpenoids and Glycosides, Steroids, Alkaloid, Phenols, Acids and Aldehydes. Natural Product Library Plus, with more powerful screening capability, further complements Natural Product Library (HY-L021) by adding some compounds with low solubility or solution stability (Part B) to this library. All those supplementary are supplied in powder form.

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 40 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.

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 195 small molecules related to dopamine receptor. It is a good tool for screening drugs from nervous system disease.

Lung cancer is a major global health problem, as it is the leading cause of cancer-related deaths worldwide. Lung cancer is divided into two categories: small cell lung cancer and non-small cell lung cancer (NSCLC). Non-small cell lung cancer accounts for about 85 percent of lung cancers.

As with all cancers, lung cancer may be treated with surgery, chemotherapy, radiation therapy, targeted therapy, immunotherapy or a combination thereof. Targeted therapy is one of the most exciting developments in lung cancer medicine, especially for NSCLC. Extensive genomic characterization of NSCLC has led to the identification of molecular subtypes of NSCLC that are oncogene addicted and exquisitely sensitive to targeted therapies. These include activating mutations in epidermal growth factor receptor (EGFR) and BRAF or echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) fusions and ROS1 receptor tyrosine kinase fusions. These are important targets for target therapy.

MCE offers a unique collection of 1835 compounds with identified and potential anti-lung cancer activity. These compounds target lung cancer’s major targets and signaling pathways. MCE anti-lung cancer compound library is a useful tool for anti-lung cancer drugs screening and other related research.

Oxygen homeostasis regulation is the most fundamental cellular process for adjusting physiological oxygen variations, and its irregularity leads to various human diseases, including cancer. Hypoxia is closely associated with cancer development, and hypoxia/oxygen-sensing signaling plays critical roles in the modulation of cancer progression.

Hypoxia-inducible factor 1 (HIF-1) is a transcription factor that functions as a master regulator of oxygen homeostasis. A variety of HF-1 target genes have been identified thus far which encode proteins that play key roles in critical developmental and physiological processes including angiogenesis/vascular remodeling, erythropoiesis, glucose transport, glycolysis, iron transport, and cell proliferation/survival.

HIF-1 is a heterodimeric transcription factor consisting of a constitutively expressed β-subunit and an oxygen-regulated α-subunit. The unique feature of HIF-1 is the regulation of HIF-1α expression and activity based upon the cellular O₂ concentration. Under normoxic conditions, hydroxylation of HIF-1α on these different proline residues is essential for HIF proteolytic degradation by promoting interaction with the von Hippel-Lindau tumor-suppressor protein (pVHL) through hydrogen bonding to the hydroxyproline-binding pocket in the pVHL β-domain. As oxygen levels decrease, hydroxylation of HIF decreases; HIF-1α then no longer binds pVHL, and becomes stabilized, allowing more of the protein to translocate to the cell’s nucleus, where it acts as a transcription factor, upregulating (often within minutes) the production of proteins that stimulate blood perfusion in tissues and thus tissue oxygenation.

MCE offers a unique collection of 2507 oxygen sensing related compounds targeting HIF/HIF Prolyl-Hydroxylase, MAPK/ERK, PI3K/AKT signaling pathways, etc. MCE Oxygen Sensing Compound Library is a useful tool to study hypoxia, oxidative stress and discover new anti-cancer drugs.