GPCRs

According to reports, most known kinase inhibitors exert their effects through competitive binding in highly conserved ATP pockets. Although genetic techniques such as RNA interference can inactivate specific genes, most kinases are multi domain proteins, each of which has an independent function. Highly selective inhibitors have higher efficiency than non-selective inhibitors, and the selectivity to the target is at least 100 times higher. Therefore, ensuring the validation of targets with the most selective inhibitors is crucial for a more thorough understanding of the pharmacology of the kinase field. The Highly Selective Inhibitors Library contains 6,342 compounds, covering multiple targets and subtypes, such as GPCR protein family, Ion channel, multiple kinases, etc. The Highly Selective Inhibitors Library is an effective tool for screening different phenotypes

Membrane receptors, also known cell surface receptors or transmembrane receptors, are transmembrane proteins embedded into the plasma membrane which play an essential role in maintaining communication between the internal processes within the cell and various types of extracellular signals. They act in cell signaling by receiving (binding to) extracellular molecules, which are also called ligands. These extracellular molecules include hormones, cytokines, growth factors, neurotransmitters, lipophilic signaling molecules such as prostaglandins, and cell recognition molecules.

There are three kinds of membrane receptors: ion channel-linked receptors, enzyme-linked receptors and G-protein-linked receptors. They play important roles in keeping human normal physiologic processes. GPCRs and ion channels are important drug targets in drug discovery.

MCE provides a unique collection of 7,133 compounds targeting a variety of membrane receptors. MCE Membrane reeptor-targeted Compound Library can be used for membrane receptor-focused screening and drug discovery.

5-HT receptors, also called Serotonin receptors, are a group of G protein-coupled receptors (GPCRs) and ligand-gated ion channels (LGICs) found in the central and peripheral nervous systems. These receptors are now classified into seven families, 5-HT1–7, comprising a total of 14 structurally and pharmacologically distinct mammalian 5-HT receptor subtypes. The 5-HT receptors influence various biological and neurological processes such as aggression, anxiety, appetite, cognition, learning, memory, mood, nausea, sleep, andthermoregulation. The serotonin receptors are the target of a variety of pharmaceutical drugs, including many antidepressants, antipsychotics, anorectics, antiemetics, gastroprokinetic agents, antimigraine agents, hallucinogens, and entactogens.

MCE 5-HT Receptor Compound Library consists of 430 5-HT receptor inhibitors and activators, which can be used for neuropsychiatric disorders drugs discovery.

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 1,170 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.

Orthosteric sites are highly conserved, leading to poor subtype selectivity, off-target toxicity and drug resistance in traditional drugs. By contrast, allosteric sites show low conservation, high hydrophobicity, weak polarity, confined geometry and dynamic cryptic properties, granting modulators high selectivity, functional tunability and safety. Thus, allosteric therapy has become a major focus in drug discovery.

MCE curated nearly 1,000 clinical-stage allosteric modulators, analyzed PDB complex structures to identify key pharmacophores and privileged scaffolds, then designed and filtered compounds using rational “scaffold derivation + physicochemical screening” with strict property criteria. The resulting compounds show high rigidity and shape complementarity to shallow, dynamic, hydrophobic allosteric pockets.

This library comprises 4,315 diverse, lead-like compounds ideal for allosteric drug discovery and target screening, covering kinases, GPCRs and more. All are analogs of clinical-stage molecules with similarity > 0.6, combining high druggability and allosteric binding potential to support efficient early-stage R&D.

Seven-membered rings are privileged medium-sized scaffolds with distinct twist-chair conformations and greater 3D diversity than five- and six-membered rings. Their flexible conformations allow induced-fit protein binding and precise pharmacophore positioning. They also modulate Fsp³, pKa and logP to enhance solubility and permeability. Azepanes, oxepanes and benzodiazepines serve as bioisosteres for hit discovery against GPCRs, ion channels and kinases.

Widely found in plant and microbial alkaloids, seven-membered heterocycles show excellent biocompatibility and target affinity. They underpin many approved drugs for CNS, cancer and infectious diseases, including diazepam, imipramine and carbamazepine. Clinical candidates further highlight their unique value. However, high transannular strain and synthetic difficulty limit their availability, leaving them rare in standard screening libraries.

MCE 7 Membered Scaffold Library contains 2,792 structurally diverse, lead-like molecules covering azepanes, oxepanes, benzodiazepines and dibenzazepines. With varied substitutions, chiral centers and synthetic accessibility, it fills the shortage of medium-ring scaffolds. Ideal for HTS, virtual screening and SAR studies, these novel, patent-clear compounds offer a distinctive starting point for drug discovery in CNS disorders, oncology, antivirals and challenging targets such as PPIs.

DEL technology enables the simultaneous screening of millions or billions of compounds in a single tube by covalently linking each small molecule with a unique DNA sequence. Traditional DEL screening primarily focuses on identifying non-covalent binding molecules, where interactions with the target are reversible. In contrast, DNA‑encoded covalent library is an ultra‑high‑throughput screening library developed on the basis of conventional DNA‑encoded library technology. It incorporates controllable electrophilic covalent warheads capable of forming irreversible covalent bonds with amino acid residues at the active sites of target proteins, including Cys, Lys, Ser, Tyr, and others. This covalent binding enhances binding affinity, prolongs residence time at the target site, and has the potential to overcome challenges associated with traditional non-covalent inhibitors, such as drug resistance or off-target effects.

Each compound in the library contains both a binding domain and an electrophilic warhead. It first recognizes and binds to the target through non covalent interactions, and then forms a stable covalent bond with key amino acid residues to achieve irreversible inhibition. This library is specifically designed for the discovery of potent, long lasting, and highly selective covalent inhibitors, particularly for undruggable targets such as kinases, GPCRs, proteases, and mutant oncoproteins. Each molecule is uniquely labeled with a DNA barcode for molecular identification and sequencing decoding.

This library is an advanced and highly diverse collection, consists of 35 independent sub-libraries with a total scaleof 14 million compounds, It incorporates over 14 experimentally validated covalent warheads capable of targeting cysteine, lysine, arginine, aspartic acid and glutamic acid. This library is constructed with diverse drug like core scaffolds and integrated controllable covalent warheads, it features structural diversity, reaction spec

MCE-18 stands for Medicinal Chemistry Evolution 2018, which was first published in Journal of Medicinal Chemistry in 2019 for assessing molecular novelty and three-dimensional complexity. Developed based on Clarivate global pharmaceutical patent database, this descriptor was constructed via big-data analysis covering 28,161 patented lead compounds, 1,370 approved drugs and nearly 30,000 preclinical-to-phase III drug candidates from 23 top pharmaceutical companies worldwide between 1950 and 2018, followed by structural clustering and removal of redundant outdated scaffolds for data denoising. Its scoring system integrates five core structural features including aromatic ring (AR), aliphatic heterocycle (NAR), chiral center (CHIRAL), spiro atom (SPIRO), cyclic and acyclic sp³ carbon ratio together with a quadratic topological correction factor. Breaking the limitations of the single Fsp³ parameter, MCE-18 effectively distinguishes conventional flat aromatic scaffolds from modern 3D-enriched novel chemotypes, overcoming typical drawbacks of traditional compound libraries such as scaffold redundancy, low screening hit rates and poor compatibility with allosteric and PPI-related difficult targets.

This library contains over 37,000 structurally diverse compounds with favorable overall drug-likeness, suitable for high-throughput screening against canonical targets including kinases, GPCRs and proteases as well as challenging allosteric and PPI targets. Compounds comply with the developmental trend of modern novel drug discovery, supporting routine primary screening as well as early hit identification of allosteric modulators and PPI inhibitors, serving as an efficient screening resource for early-stage innovative drug discovery.

MCE 18 stands for Medicinal Chemistry Evolution 2018. This metric was established based on structural data of 28,161 patented lead molecules, 1,370 marketed innovative drugs, and nearly 30,000 investigational candidates from preclinical to Phase III stages across 23 major global pharmaceutical companies from 1950 to 2018. After scaffold clustering analysis, a scoring model was constructed by integrating five three dimensional scaffold characteristics, including aromatic rings (AR), non aromatic heterocycles (NAR), chiral centers (CHIRAL), spirocycles (SPIRO), and the sp³ carbon ratio in cyclic and acyclic moieties, enabling quantitative assessment of molecular scaffold novelty and three dimensional complexity.

According to the score distribution of patented molecules, the top 25% of the original patent dataset was defined as the high novelty region. MCE 18 high scoring compounds selected based on this criterion can effectively avoid scaffold patent conflicts and intellectual property risks from the source. Molecules in this range typically feature a high sp³ carbon ratio, abundant chiral centers, spirocycles, and fused heterocycles with prominent three dimensional conformations. Their spatial properties allow precise matching to complex non traditional undruggable target pockets such as PPI interfaces and allosteric sites, making them ideal structural types for early stage screening of First in class drugs.

MCE‑18 Novelty Focused drug‑Like library strictly selects molecules from the aforementioned high scoring range, containing more than 10,000 premium drug like molecules with highly diverse scaffolds and rich 3D diversity. It can be used for high throughput screening of well established targets such as kinases, GPCRs, and proteases, and is especially suitable for hit identification in allosteric modulation, protein–protein interactions, and various undruggable orphan targets, fully supporting early stage drug discovery for cutting edge innovat