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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 4,310 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.

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 2,253 high-structurally diverse 'RO3' compliant fragment molecules from large-scale fragment molecules, which can be applied to fragment based drug development.

Targeted cancer therapies are drugs or other substances that block the growth and spread of cancer by interfering with specific molecular targets that are involved in the growth, progression, and spread of cancer.

There are several different types of targeted therapy. The most common types are small-molecule drugs and monoclonal antibodies. Small-molecule drugs are small enough to enter cells easily, so they are used for targets that are inside cells, while monoclonal antibodies are usually used for targets that are located outside the cells. Because of high specificity, low side effect and potent anticancer activity, targeted therapy has become the mainstream of new anti-tumor drugs. Various targeted therapies have been approved by FDA and used in the treatment of diseases.

MCE carefully collects a unique of 108 targeted therapy drugs used in cancer treatment. MCE Targeted therapy drug library is a useful tool for the research of targeted therapy.

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

MCE designs a unique collection of 23,342 fragment compounds, all of which obey a heuristic rule called the “Rule of Three (RO3) ”, in which molecular weight ≤300 Da, the number of hydrogen bond donors (H-donors) ≤3, the number of hydrogen bond acceptors (H-acceptors) is ≤3 and cLogP is ≤3. This library is an important source of lead-like drugs.

Hormones are a class of biologically active substances secreted by endocrine gland cells, which are transported through the circulatory system to various parts of the body, and precisely act on specific target organs or cells, playing a crucial role in regulating the growth, development, metabolism, and reproduction of organisms. The mechanisms of hormone action are diverse and complex. Some hormones (such as corticosteroids, vitamin D, and thyroid hormones) can enter the cell interior and interact with receptors in the nucleus, thereby regulating gene expression and affecting cell function. Other hormones (such as growth hormone and thyrotropin-releasing hormone) bind directly to receptors on the cell surface, exerting their effects by regulating enzyme activity or influencing the state of ion channels. Additionally, hormones play a key role in the study of endocrine and metabolic diseases, and are closely related to the development of diseases such as diabetes and thyroid diseases.

MCE has included 86 human hormone compounds, which is of great significance for the study of human metabolic pathways, and can also be used to build a metabonomics database.

Bioactive small molecules are important sources of lead compounds and effective tools for drug screening. Because the target of active small molecules is clear, it is conducive to the study of mechanism. In addition, due to the large structural differences between the individual active molecules, it is easier to obtain a greater variety of lead compounds.

MCE integrates the Bioactive Compound Library (HY-L001) and Novel Bioactive Compound Library (HY-L111) to form the Bioactive Compound Library Max. Bioactive Compound Library Max contains novel active small molecules, molecules that have entered the clinical stage and the market, and small molecules that have been verified by cell experiments or biochemical experiments, which fundamentally expands the number of compound libraries in the library and improves the structural diversity, and is an effective tool to start drug screening and mechanism research.

MCE can provide a library of 29,173 mitophagy compounds, which can be used for drug development and mechanism research in cancer, immunity, infection and other hot research fields.

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

MCE designs a unique collection of 2,174 smal-molecule modulators that can be used for the research of Ion Channel and Membrane Transporter or high throughput screening (HTS) related drug discovery.

Ionizable lipids are a class of specialized, functional lipid molecules with pH-sensitive charge characteristics. They are primarily divided into two major categories: ionizable cationic lipids and ionizable anionic lipids, though the term typically specifies ionizable cationic lipids within the biomedical field. Structurally, these lipids consist of an ionizable hydrophilic headgroup, a biodegradable linker, and hydrophobic tails. Their primary application is serving as the key delivery vehicle in lipid nanoparticles (LNPs) to encapsulate negatively charged nucleic acid macromolecules, such as mRNA vaccines, siRNA therapeutics, and CRISPR gene-editing components. In a physiological, neutral environment, they remain electrically neutral to minimize systemic toxicity and prolong circulation time. Upon entering the acidic microenvironment of cellular endosomes, however, they undergo protonation to become positively charged, thereby inducing membrane fusion and enabling the highly efficient intracellular release of the nucleic acid cargo. Consequently, they serve as the technological cornerstone for bringing nucleic acid therapies into clinical application.

To accelerate the translational process of cutting-edge nucleic acid drugs, MCE has meticulously constructed an ionizable lipid compound library containing 95 high-performance molecules, aiming to provide researchers and pharmaceutical professionals with a high-throughput, multi-dimensional lipid screening platform.

With the aging population and increasing competitive pressures, neurodegenerative diseases of the central nervous system (CNS) have become a serious medical challenge in modern society, including Parkinson's disease, Alzheimer's disease, brain tumors, and multiple sclerosis. However, the success rate of CNS drug development remains remarkably low, primarily due to the blood-brain barrier (BBB). The blood-brain barrier (BBB) is a semipermeable barrier structure that surrounds the microvasculature of the CNS. In capillaries, the wedged endothelial cells are tightly packed and wedge-shaped, lining the interior of the vessels to form extensive tight junctions. Along with a range of receptors, transporters, efflux pumps, and other cellular components, this barrier regulates the entry and exit of molecules between the bloodstream and the brain. The intact BBB blocks the passage of most blood-borne substances into the brain, preventing nearly 100% of large-molecule drugs and over 98% of small-molecule drugs from entering. Compared to non-CNS drugs, physicochemical properties such as hydrogen bonds, lipophilicity, and molecular weight significantly influence a compound's ability to cross the BBB. Using artificial intelligence (AI) algorithms to predict BBB permeability, a predicted value greater than 0.75 indicates that the compound has strong potential to cross the BBB, providing a promising starting point for CNS drug discovery.

In contrast to the high conservation of conventional orthosteric sites, allosteric sites possess structural characteristics of low conservation, high hydrophobicity, weak polarity, confined spatial geometry, and dynamic cryptic properties. There is a significant difference between their core structures and orthosteric pockets — allosteric pockets are mostly dynamic grooves formed by protein conformational changes, subunit interface clefts, or shallow depressions, rather than the rigid "keyhole" structure of orthosteric sites. With looser spatial constraints, allosteric sites have the advantages of high selectivity and low off-target risk, and have become an important direction in new drug discovery.

Based on the dynamic, hydrophobic, and narrow-long spatial characteristics of allosteric pockets, MCE has performed targeted modification and screening of fragments. The screening criteria strictly conform to the requirements of allosteric binding: molecular weight is controlled at 120–280 Da (to meet the core needs of small molecules in fragment libraries and high derivatization), hydrogen bond donors (HBD ≤ 2), hydrogen bond acceptors (HBA ≤ 3), polar surface area (PSA = 30–80 Ų), rotatable bonds (≤ 2), moderate hydrophobicity (cLogP = 1–3.5), no strongly ionizable groups, and both appropriate rigidity and conformational flexibility to adapt to the dynamic changes of the pocket. Meanwhile, combined with the results of principal moment of inertia (PMI) analysis, fragments with high 3D diversity were obtained. Such fragments have good shape complementarity with allosteric pockets, ensuring that the fragments can smoothly enter the allosteric pockets and form stable binding, while providing room for subsequent optimization and derivation.

This library contains 1,800 structurally diverse fragment molecules with excellent drug-like properties, suitable for allosteric drug development and the design and optimization of allosteric sites. It combines the

MCE Weigert Elastin Staining Kit combines Weigert Resorcinol Fuchsin Staining Solution with Van Gieson (VG) Staining Solution. Weigert Resorcinol Fuchsin Solution is mainly used for staining elastic fibers, Van Gieson (VG) Solution is used for collagen fiber staining. The principle of VG staining is based on differences in the size of anionic dye molecules and the permeability of tissues. Picric acid (PA) has the smallest molecular weight and preferentially enters dense structures. Ponceau Red or acid fuchsin has a relatively larger molecular weight and primarily binds to collagen fibers, while light green has the largest molecular weight and stains other tissue components. After VG staining, collagen fibers appear red, while muscle fibers and cytoplasm appear yellow, enabling a clear distinction between tissue components.