• A 5-minute Tour of the Coumarin Family.

    Coumarins are a group of natural products that are widely distributed in nature and have important biological activities such as anti-inflammatory, anti-edema, anti-cancer, anti-tumour and immune enhancing, anti-oxidant, scavenging excess oxygen free radicals and protecting liver cells.



  • Dioxane in Our Lives and How It Impacts

    Dioxane is used as a stabilizer for chlorinated solvents such as trichloroethane and trichloroethylene. It can also be an unintended contaminant of chemical ingredients used in consumer products including bubble bath, shampoo, laundry detergent, soap, skin cleanser, adhesives, and antifreeze. Foods may also contain small amounts of 1,4-dioxane from some additives and packaging materials.



  • Commonly Seen Cycloalkanes and Their Uses

    Cycloalkanes are saturated hydrocarbons with a cyclic arrangement of carbon atoms and a sufficient number of hydrogen atoms. Cyclopentane and cyclohexane are the main cycloalkanes in petroleum. The melting point, boiling point and relative density of cycloalkanes are higher than those of the corresponding straight-chain alkanes. Paraffin naphthenic crude oil with low sulfur content is not only easy to process, but also a good raw material for the production of high-grade lubricating oil. Petroleum, which contains more naphthenes with multi-ring long side chains, is an ideal raw material for high quality lubricating oils. CHEMENU introduces you to several commonly used cycloalkanes and their uses.



  • LINKCHEM's New Research & Development Center

    This is CHEMLINK's New Research & Development Center, we just moved there.



  • How Borates Keep Swimming Pools Clean

    Boron is a unique and exciting element. Over the years, it has proven to be a constant challenge and stimulus not only for preparative chemists and theorists, but also for industrial chemists and technicians. Borates are a family of ubiquitous flame retardants that exist as boric acid and various salts, notably sodium borate (borax) and zinc borate. Along with the sodium salt called borax, boric acid was one of the first flame retardants used. In halogen systems, zinc borate is often used as a component replacement for antimony oxide; providing possible cost savings and, in many cases, improving certain aspects of fire performance, including smoke and afterglow suppression.   Potassium (bromomethyl)trifluoroborate   Swimming Pool Maintenance It is important to maintain your pool's total alkalinity (TA) and pH at the recommended levels; if either is out of balance, it can affect the function of all chemicals in your pool, including chlorine. If you want to simplify pool maintenance by better keeping your pool's TA and pH in balance, then borates are the answer. When pH is out of balance Many situations occur when the pH of your pool water is unbalanced. Take a look at the following information.   pH level exceeds 7.8: Chlorine stops working, clouding the water and promoting the growth of water bacteria and algae. High pH levels can lead to calcium scale on pool surfaces, pipes and accessories, especially in saltwater pools. High pH levels can cause health problems such as burning eyes and nose, dry skin and scalp, and itching.   pH levels below 7.0: Erosion of pool components Plaster and grout damage Corrosion of metal fittings Metal stains Metal corrosion causing water discoloration If you don't want this to happen to your pool, you should consider adding borates to your pool. Let's take a look at some of the benefits of using borates as part of your pool maintenance.       Benefits of using borates Helps stabilize pH - Using a neutral pH borate helps stabilize the chemicals in your pool water. Helps prevent algae growth - Since borates keep the pH balanced and chlorine works effectively, algae has no room to multiply and start growing in your pool. Less chlorine - Since borates help prevent algae growth, you can use less chlorine, which means you can save money on your monthly chemical bill. Soft, shiny water - Borates help the water stay cleaner longer. Chloramines don't develop as quickly compared to those who don't include borate reagents in their pool maintenance. Good borates contain chlorine stabilizers that prevent UV light from depleting the chemicals. An added benefit - borates not only make the water healthy, but they also prevent dry skin and red, itchy eyes in swimmers.   potassium trifluoro(tetrahydro-2H-pyran-4-yl)borate   Borax Borax was known worldwide in ancient times for its use in the preparation of glazes and hard (borosilicate) glass. High purity boron (>99%) is a product of this century, and various crystalline forms have only been obtained in recent decades, mainly because of the element's highly refractory nature and its rapid reaction with nitrogen, oxygen and most metals at high temperatures. If you are going to use borax in your home, there are precautions you can take to ensure safety, such as wearing gloves and Wash your hands thoroughly after using borax. If needed, seek medical help to prevent exposure.     This is an introduction to borates and borax. If you need any other pharmaceutical intermediates or chemical products, please contact us.  



  • Where Is Benzene Found And How Is Benzene Used?

    Benzene is a colorless or yellowish liquid that evaporates rapidly when exposed to air, but it does not dissolve well in water and tends to float on top. It is produced as part of natural and man-made processes. Benzene, for example, is a natural component of crude oil and is the main source of benzene today. It is also found in forest fires, volcanoes and in gaseous emissions from cigarette smoke. When you think of the molecular formula of benzene, you immediately think of the scientific story of the chemist who was inspired to solve the structure of the benzene ring after he dreamed of a snake biting his tail. The chemical formula for benzene is C6H6, and the benzene molecule consists of six carbon atoms in a ring with a hydrogen atom attached to each carbon atom. Since it contains only carbon and hydrogen atoms, benzene is classified as a hydrocarbon.     Where is benzene found Benzene is formed by natural processes and human activities. Natural sources of benzene include volcanoes and forest fires. Benzene is also a natural component of crude oil, gasoline and cigarette smoke.     How Benzene is used Benzene is one of the top 20 most widely used chemicals in the United States. It is used primarily as a starting chemical in the manufacture of other products and is often used to make chemicals that are later used in other products. Common examples include:   Plastics Nylons Resins Dyes Lubricants Synthetic fibers Detergent Rubber Pesticides Gasoline It is mainly used as a solvent in the pharmaceutical industry and can be found in certain drugs. Historically, benzene has also been used as an industrial solvent and gasoline additive, although these uses have declined dramatically over the past few decades.       How people are exposed to benzene Most people are exposed to benzene through inhalation because benzene evaporates rapidly when it comes into contact with air. Benzene can also be absorbed through the skin when in contact with liquid sources containing benzene, but this is less common. Historically, the highest exposure levels have been in workplaces in industries that use benzene. That said, many industries are reducing the use of benzene, so this has declined in recent years. The general population is more likely to be exposed to benzene through inhalation of tobacco smoke, particularly through cigarettes. In fact, among smokers, 90% of benzene exposure comes from inhaling cigarette smoke. Benzene is also found in gasoline and can be inhaled if someone breathes in gasoline fumes. It can also be found in glues, adhesives, paint strippers and cleaning products. As a best practice, it is recommended that benzene be evaluated by a third-party petroleum and chemical testing laboratory to ensure that it is completely safe for use.     3-(methoxycarbonyl)-2-aminobenzoic acid   Uses of benzene in pharmaceuticals It is primarily used as a solvent in the pharmaceutical industry and can be found in some drugs. Historically, benzene has also been used as an industrial solvent and gasoline additive, although these uses have declined dramatically over the past few decades. The benzene series is the most important group of aromatics. It is a series of hydrocarbons based on the benzene ring with the general formula CnH2n-6, where 'n' is 6 or greater. Examples include benzene (C6H6), toluene (C7H8) and xylene (C8H10). The first three members of the series of particular interest are benzene, toluene and xylene, which are clear, colorless liquids with very similar properties at room temperature. Crude benzene also contains some amount of naphthalene (C10H8).     Crude benzene is a product of the dry distillation process of coking coal. Benzene (also called benzene) is the name commonly used in the chemical industry for a mixture of benzene hydrocarbons in which benzene itself predominates, together with certain of its congeners and various impurities. The term does not apply to any particular mixture or liquid mass. Recovery of benzene from coke oven gas means removing the benzene series vapors and then converting them into different liquid products by condensation.     CHEMENU is a professional API and API producer, we have many other benzene compounds for sale, feel free to contact us.



  • Anthracene: Structure, Usage and Hazards

    Anthracene is a colorless crystalline aromatic hydrocarbon used in the chemical industry and is produced by distilling natural crude oil. This blog will explore its structure, the reactions it undergoes, its uses and hazards.   Aromatic compounds Anthracene is a polycyclic aromatic hydrocarbon with three thickly packed benzene rings. Sarah breaks it down very simply: polycyclic means there is more than one ring, aromatic means the molecule has alternating double single bonds around the ring system, and hydrocarbon means it consists of only carbon and hydrogen atoms. We note the three rings connected together, with a network of alternating double and single bonds around the three rings.   9,10-dibromoanthracene   Dimerization of anthracene If we expose anthracene to UV light, it will actually undergo what is called a dimerization reaction. This is when two anthracene molecules combine with each other to form a larger hydrocarbon structure. In terms of applications, compounds such as anthracene dimers and other polycyclic aromatic hydrocarbons play an important role in organic semiconductors. In addition, they have received a great deal of attention from researchers as organic materials that can be used in solar panels to harness the sun's energy.   Oxidation of anthracene If anthracene is reacted with an oxidizing agent such as hydrogen peroxide, the product we get is anthraquinone. Anthraquinone is easy to identify; it is simply anthracene with two carbon-oxygen double bonds on the two middle carbons of the molecule.   4,8-diamino-2-bromo-1,5-dihydroxy-9,10-dihydroanthracene-9,10-dione   Uses of anthracene Some of the most common applications of anthracene include use as a preservative for wood and timber and as a pesticide for crops. The product anthraquinone is actually used as a component of many of the dyes that the fabric and textile industries rely on for their vibrant colors. Anthracene is used as a scintillator for high-energy photon, electron and alpha particle detectors. Plastics, such as polyethylene-based toluene, can be doped with anthracene to create a water-equivalent plastic scintillator for radiation therapy dosimetry.   Anthracene is widely used as a UV tracer in conformal coatings for printed circuit boards. Anthracene tracers allow UV detection of conformal coatings. Anthracene is also used for anthraquinone applications.   Anthracene derivatives are used in many applications. 1-hydroxyanthracene and 2-hydroxyanthracene are hydroxylated derivatives of phenol and naphthol, and hydroxyanthracene (also known as anthracenol and anthracenol) has pharmacological activity. 9,10-dihydroxyanthracene is an example of anthracene with several hydroxyl groups.   (10-phenylanthracen-9-yl)boronic acid   Attention to hazards Anthracene is a non-carcinogenic substance. PAHs are considered to be potential starting materials for the abiotic synthesis of materials needed for the earliest forms of life. When inhaled, anthracene can irritate the throat, nose and lungs, causing wheezing and coughing. Contact with the skin may cause irritation, burns, and itching caused by sunlight. Frequent exposure may lead to skin thickening and pigmentation changes. Studies have shown that anthracene may become allergic, and once the allergy is fully developed in an individual, even very low future exposures can cause a rash. Please note that local exhaust ventilation is used in areas where chemicals are released. If local exhaust ventilation is not appropriate for the job, make sure you use a respirator that is easy to wear.     Contact supplier CHEMENU to buy the APIs you want.



  • ADC Cytotoxins, Antibody-drug Couples and Efficacy Assays

    ADC Cytotoxins,antibody-drug couples and Efficacy Assays   ADC cytotoxins are cytotoxic agents that induce the death of target cells in antibody drug couples (ADCs), which are targeted drugs consisting of monoclonal antibodies, connectors and cytotoxins. The cytotoxin is the most important component, as it determines the ability of ADCs to kill cancer cells.   Many cytotoxins are currently being used, such as galicin, doxorubicin, pyrrolobenzodiazepines (PBD), camptothecin, erythromycin/doxorubicin, Auristatins, and medensin. Based on their mechanism of action, they can be divided into two categories: DNA damaging agents and microtubulin inhibitors. Among them, galicin, doxorubicin and PBD are DNA grove-binding agents, and hippocrine and erythromycin/doxorubicin are topoisomerase inhibitors, which are DNA damaging agents. auristatins and maytansinoids are microtubule protein inhibitors. In addition to the listed cytotoxins, there are many traditional cytotoxic agents with similar mechanisms of killing cancer cells that can also be used in the development of ADCs. ADC cytotoxins are cytotoxic agents that induce the death of target cells in antibody drug couples (ADCs), which are targeted drugs consisting of monoclonal antibodies, connectors and cytotoxins. The cytotoxin is the most important component, as it determines the ability of ADCs to kill cancer cells.   Many cytotoxins are currently being used, such as galicin, doxorubicin, pyrrolobenzodiazepines (PBD), camptothecin, erythromycin/doxorubicin, Auristatins, and medensin. Based on their mechanism of action, they can be divided into two categories: DNA damaging agents and microtubulin inhibitors. Among them, galicin, doxorubicin and PBD are DNA grove-binding agents, and hippocrine and erythromycin/doxorubicin are topoisomerase inhibitors, which are DNA damaging agents. auristatins and maytansinoids are microtubule protein inhibitors. In addition to the listed cytotoxins, there are many traditional cytotoxic agents with similar mechanisms of killing cancer cells that can also be used in the development of ADCs.     Aldoxorubicin CAS:1361644-26-9     Antibody-drug couples or ADCs combine the selectivity of antibodies with the efficacy of small molecule drugs to enable more precise and targeted therapeutic applications. Over the past two decades, researchers have also explored opportunities to develop ADCs into disease indications other than cancer, including autoimmune diseases, difficult-to-treat bacterial infections, and atherosclerosis. However, in order to successfully develop these non-oncology ADCs, many challenges need to be addressed in order to realize the greater promise of ADC technology.   To date, seven ADCs have been approved by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) and are commercially available to meet patient needs; all carry cytotoxic payloads against a variety of liquid and solid tumors.     Ansamitocin P 3', CAS:66547-09-9     ADC Cytotoxicity Assays The in vitro efficacy of antibody-drug couples (ADCs) is an important parameter in ADC development programs. This is the first qualitative assessment of ADC drug efficacy, and it provides a baseline for ADC improvement. The new generation of ADCs benefits from a series of improvements in payload potency, site-specific coupling strategies and innovative chemical junctions. ADCs deliver excellent antitumor efficacy while improving normal tissue safety. Good ADC efficacy in vitro and in vivo is a major concern for any ADC development program, as it is the ultimate goal of preclinical studies and a prelude to clinical evaluation.   The in vitro efficacy of ADCs, especially their cytotoxicity, must be fully evaluated before in vivo activity/efficacy assessment can be performed. In vitro cytotoxicity assays are widely used for this purpose. In this set of assays, ADC toxicity was tested against a variety of tumor cell lines expressing the targeted surface antigens.The in vitro efficacy of ADCs was directly reflected by cell viability assays, in which the total number of viable cells after ADC exposure was assessed by various organic dyes. In addition, other assays such as apoptosis and cell cycle assays were used to analyze and confirm the subcellular targets and working mechanisms of ADC. Last but not least, when assessing the in vitro effectiveness of ADCs, normal cells are also involved in the assay to assess the in vitro safety of the ADCs tested.     MMAF Sodium,CAS:1799706-65-2       Today, a new chapter is being written in the long story of antibody-drug couples. As the understanding of ADC technology continues to grow, it is foreseen that the development of these compounds in disease therapeutic areas beyond the fields of oncology and hematology will increase rapidly. Some of these novel ADCs will be developed for therapeutic purposes and some as precursors or modulators for further treatments. Please contact Chemenu to find the quote.



  • What You Need to Know about Peptides and Their Benefits

    Peptides are smaller versions of proteins. Many health and beauty products contain different peptides for multiple uses, such as their potential anti-aging, anti-inflammatory or muscle building properties. People may confuse peptides with proteins. Both proteins and peptides are made up of amino acids, but peptides contain far fewer amino acids than proteins. Like proteins, peptides are naturally found in foods. Because of the potential health benefits of peptides, many supplements contain peptides that are derived from food or manufactured synthetically by the manufacturer. In this article, we discuss the potential benefits of peptide supplements.     What are peptides? Peptides may help build strength and muscle mass. A peptide is a very short string of amino acids, usually containing 2-50 amino acids. Amino acids are also part of proteins, but proteins contain more. Peptides may be more readily absorbed by the body than proteins because they are smaller and more easily broken down than proteins. They can penetrate the skin and intestines more easily, which helps them enter the bloodstream more quickly. Scientists are most interested in bioactive peptides, or those peptides that are beneficial to the body and may have a positive impact on human health. Different bioactive peptides have different properties. Their effect on the body depends on the amino acid sequence trusted source they contain.     Uses and benefits Possible benefits of peptides include reducing inflammation, improving immune function and preventing thrombosis. Peptides are often used to try to achieve the following effects.   Slow down the aging process Collagen is a protein found in the skin, hair and nails. Collagen peptides are broken down collagen that is more easily absorbed by the body. Taking collagen peptides can improve skin health and slow down the aging process. Some studies from credible sources suggest that dietary supplements containing collagen peptides can treat skin wrinkles. Other studies have shown that these supplements can also improve skin elasticity and hydration.   (2R)-2-amino-3-(thiophen-2-yl)propanoic acid   Improves wound healing Because collagen is an important component of healthy skin, collagen peptides can promote faster wound healing. Bioactive peptides can also reduce inflammation and act as antioxidants, thereby improving the body's ability to heal. Antimicrobial peptides are currently being investigated, which may also improve wound healing. Very high or very low levels of certain antimicrobial peptides may contribute to skin conditions such as psoriasis, rosacea and eczema.   Prevention of bone loss Trusted sources of animal studies have linked moderate intake of collagen peptides to increased bone mass in growing rats that also perform running exercises. This study may point to collagen peptides as a useful way to combat age-related bone loss. However, more research is needed, especially in humans.   Strength enhancement Several studies with credible sources on older adults have shown that collagen peptide supplements can increase muscle mass and strength. In this study, participants combined the use of supplements with resistance training. Creatine peptides may also improve strength and help build muscle. While fitness enthusiasts have been using creatine protein powders for years, creatine peptides are becoming increasingly popular. These particular peptides may be easier for the body to digest, which means they may cause fewer digestive problems than creatine protein.   (2S)-2-amino-2-cyclopropylacetic acid   OVERVIEW Peptides are naturally occurring in protein-rich foods. There is no need to take peptide supplements or use topical sources of peptides. There is still limited evidence that these products are effective, and more research is needed to thoroughly evaluate their efficacy and safety. Research on peptides is still in its early stages, and in the future, scientists may discover the health benefits of different types of peptides. Until then, people should exercise caution when taking any supplement and discuss the potential benefits and risks with their doctor beforehand.   Please contact Chemenu if you need to buy them.    



  • Three Major Classifications of Aliphatic Hydrocarbons

    Hydrocarbons, any class of organic compounds consisting only of the elements carbon (C) and hydrogen (H). The carbon atoms are joined together to form the framework of the compound, and the hydrogen atoms are attached to them in many different configurations. Hydrocarbons are the main components of oil and natural gas.   Many hydrocarbons are found in nature. In addition to making up fossil fuels, they are found in trees and plants, for example, in the form of pigments called carotenoids in carrots and green leaves. More than 98% of natural crude rubber is a hydrocarbon polymer, a chain-like molecule consisting of many linked units. The structure and chemical properties of individual hydrocarbons depend greatly on the type of chemical bonds that hold the atoms of their constituent molecules together.   Aliphatic hydrocarbons are divided into three main groups based on the type of bonds they contain: alkanes, alkenes and alkynes. Alkanes have only single bonds, alkenes contain carbon-carbon double bonds, and alkynes contain carbon-carbon triple bonds. Aromatic hydrocarbons are those that are more stable than their Lewis structure would suggest; that is, they have "special stability. They are classified as either arenes, which contain a benzene ring as a structural unit, or non-benzene aromatic hydrocarbons, which have special stability but lack a benzene ring as a structural unit.   Isopropenoxytrimethylsilane, CAS:1833-53-0     This classification of hydrocarbons helps to relate structural features to properties, but it is not necessary to assign specific substances to a single category. In fact, a molecule usually contains two or more structural units characteristic of the hydrocarbon group. For example, a molecule that contains both a carbon-carbon triple bond and a benzene ring will exhibit some of the properties of an alkyne and the properties of an aromatic hydrocarbon.     Alkanes Alkanes are hydrocarbons in which all bonds are single bonds and whose molecular formulae satisfy the general expression C n H 2 n + 2 (where n is an integer). The carbon is s p 3 hybridized and each C-C and C-H bond is a σ-bond. Methane (CH 4), ethane (C 2 H 6 ), and propane (C 3 H 8 ) are the first three members of the series in increasing order of carbon atom number.   2-ethoxy-2-oxoacetonitrile, CAS:623-49-4   Cycloalkanes Countless organic compounds are known in which a series of carbon atoms are not joined in a chain but closed to form a ring. A saturated hydrocarbon containing a ring is called a cycloalkane. The general formula is C n H 2 n (n is an integer greater than 2), and they have two fewer hydrogen atoms than alkanes with the same number of carbon atoms. Cyclopropane (C 3 H 6 ) is the smallest cyclic alkane.     Olefins and alkynes Olefins (also called olefins) and alkynes (also called acetylenes) belong to the group of unsaturated aliphatic hydrocarbons. Olefins are hydrocarbons containing carbon-carbon double bonds, while alkynes have carbon-carbon triple bonds. Olefins are characterized by the general formula C n H 2 n and alkynes are characterized by C n H 2 n - 2. Ethylene (C 2 H 4 ) is the simplest olefin and acetylene (C 2 H 2 ) is the simplest alkyne.       Hydrocarbons are the main components of oil and natural gas, and they are used as fuels and lubricants and as raw materials for the production of plastics, fibers, rubber, solvents, explosives, and industrial chemicals that are important raw materials in our lives.   To buy the raw materials and get more info about APIs, please contact Chemenu.




    New drug research and development is very difficult, and there is a saying that "it takes an average of ten years and one billion dollars to develop a new drug". Traditional R&D is complicated and costs continue to rise.



  • Advantages of PROTAC Technology and PROTAC Linker

      In recent years, global drug sales trends show that biologics have started to take off, while small molecule drugs are declining, and there is an urgent need to introduce revolutionary new technologies for small molecule drug development. With the continuous development and improvement of PROTAC technology, it has gone from unrecognized to highly sought-after, and has now gained the favor of many international pharmaceutical giants.       PROTAC Technology Protein Degradation Targeted Chimeras (PROTAC) is a technology that can be said to have its roots in the Nobel Prize in Chemistry. The degradation or intervention of disease-causing proteins has become one of the most effective disease treatment strategies available. Since the human genome was decoded, researchers have been trying to target the thousands of proteins that cause disease. It is estimated that only 10% of proteins can be regulated by small molecules, 10% of proteins that can be regulated by biomolecules are on the cell surface, and up to 80% of proteins cannot be regulated by existing drugs. Targeted protein degradation drugs seek to engineer small molecules into a new class of drugs, where traditional small molecules act by blocking the function of proteins, while targeted protein degradation agents act by delivering these proteins into the proteasome where they are completely degraded.   Propargyl-PEG2-OH,  CAS:7218-43-1   Research Progress By the end of 2021, about a dozen PROTACs are in clinical development worldwide, and there are about 110 programs in preclinical development. In the whole development field, some R&D startups have gained the attention of global large pharmaceutical companies such as Roche, Sanofi, Merck Sharp & Dohme, Pfizer and Gilead, and are collaborating on protein degradation therapies; meanwhile, domestic companies are also actively involved in the development, showing a booming trend.   PROTAC Technical Advantages PROTAC largely combines the advantages of small molecule compounds and small molecule nucleic acids. PROTAC theoretically requires only a catalytic amount of drug and can also selectively degrade different proteins expressed in the same gene after protein expression and modification, so there are certain theoretical advantages.   Fmoc-amino-PEG3-CH2COOH,  CAS:139338-72-0     Disadvantages of PROTAC technology These drugs are dual-target drugs, so their molecular weight, molecular rigidity, and water solubility are not ideal, so oral absorption and transmembrane properties are poor, and PROTAC molecules are usually very large, and PK is a major obstacle. Overall, PK remains a major barrier to drug formation for most small PROTAC molecules. Chemical synthesis is also much more difficult. Off-target toxicity should also be one of the biggest concerns. PROTAC, as more thorough target protein degraders, may accidentally injure other off-target proteins. Even if it is a previously validated target, whether it will bring more serious toxicity in the future needs to be closely monitored in clinical trials.       CHEMENU, a provider of PROTAC-linker bioactivity assay solutions, offers you the most professional solutions to help you accelerate your PROTAC development.    



  • Application of Piperidine in Drug Molecular Design

    Piperidine is a saturated heterocyclic secondary amine that is an important pharmacodynamic group as well as a dominant backbone with a variety of biological activities, such as antibacterial, anti-inflammatory, antiviral, antimalarial, general anesthetic, antidepressant, antioxidant, antiepileptic, antitumor, anticonvulsant, and antihyperlipidemic. Like many nitrogen-containing groups, piperidine is able to form additional interactions with targets, can easily cross cell membranes, solve drug resistance problems, can increase the water solubility of drug molecules, and is the most common group in drug molecule design.   The azepidine ring is one of the most important structural components in drugs. An analysis of the US FDA database of approved drugs shows that 59% of unique small molecule drugs contain nitrogen heterocycles. Among the most prevalent nitrogen ring systems, the drugs containing piperidine rings were the most abundant, followed by pyridine and piperazine.       Marketed drugs A number of small molecule drugs that have been approved for marketing in recent years also contain piperidine rings. For example, Rimegepant is a calcitonin gene-related peptide (CGRP) receptor antagonist used in the acute treatment of migraine in adults. Revefenacin is an inhaled muscarinic receptor antagonist, which was launched in the United States in 2018 for the maintenance treatment of chronic obstructive pulmonary disease (COPD). Lasmiditan succinate is an oral 5-HT1F receptor agonist and is a class of neurologically acting anti-migraine drugs (NAAMA). Dacomitib, a pan-human epidermal growth factor kinase inhibitor, was first marketed in the United States in 2018 as a first-line oral treatment for metastatic non-small cell lung cancer (NSCLC) with EGFR exon 19 deletion or 21 L858R exon substitution mutations.     Drug structure optimization Many of the drugs under development also contain piperidine rings as pharmacodynamic groups that play an important role in enhancing the interaction with the target and improving the pharmacokinetic properties.     1. piperidine ring increases the water solubility of the drug In addition to being part of the drug's pharmacodynamic group, piperidines have been used to increase the water solubility of the drug. Since the pKa of piperidine itself is 11.22, the pKa of n-alkylated piperidine is about 9.5. Installing piperidine rings has been routinely used to increase the water solubility of drugs. For example, 4-aminoquinazoline 46 is a potent kinase insertion domain receptor (KDR) inhibitor but has poor solubility (0.7 μM). A basic piperidine ring was installed on the side chain to replace the triazole, which resulted in a 500-fold increase in solubility (330 μM) at pH 7.4 (physiological acidity).   2. Piperidine ring solves the problem of drug resistance Pgp (permeability glycoprotein) is the most common drug efflux transport protein, which is often overexpressed in tumor cells and is one of the causes of multidrug resistance. Half of the marketed drugs are Pgp substrates. One strategy to address the Pgp problem is to improve the log P of the drug to reduce penetration into the lipid bilayer. The tetracyclic compound48 is a chemotherapeutic drug that has resulted in cytotoxic resistance due to its use as a Pgp substrate.48 The Mannich reaction of 48 was obtained with a modified 3-aminomethylpiperidine derivative.49 This structural change gives the piperidine compound activity against tumor cells.       CHEMENU provides a wide variety of organic compounds and offers exclusive development for advanced intermediates. We manufacture building blocks, intermediates and novel compounds.Please click the button to get in touch with us.  



  • Nucleoside Drugs and APIs: for the Teatment of Hepatitis B

    The nucleoside drugs has been instrumental in the treatment of chronic hepatitis B. In the past two decades, research has continued to develop and nucleoside analogues have emerged, and there are now five nucleoside analogues, including lamivudine, adefovir, tipifovir, entecavir and tenofovir, and people have gained a deeper understanding and more experience in the antiviral treatment of hepatitis B. With the end of the protection period of various original drugs, the research and development of generic drugs in China has entered a brand new stage, and clinicians and patients have more choices compared with the past.   CHEMENU is a manufacturer of nucleoside and nucleotide pharmaceutical ingredients, and we have various intermediates for sale to provide basic materials for the research of nucleoside drugs in the world. Read on to learn more about how nucleosides are therapeutic.         The importance of treatment Antiviral treatment for chronic hepatitis B is a global consensus. Although hepatitis B virus does not directly destroy liver cells, liver cells are the host site of hepatitis B virus, and once the body's immune system recognizes hepatitis B virus, an immune-mediated response is bound to occur, causing liver cell damage, abnormal liver function, and even cirrhosis, liver failure, and possibly liver cancer. Therefore, various guidelines from around the world emphasize the necessity and importance of antiviral therapy for chronic hepatitis B.   There are two major categories of clinically applied anti-hepatitis B virus drugs, one is nucleoside analogues and the other is a-interferon, the latter has a tendency to gradually decrease in clinical application because of the large side effects and inconvenient administration, and the more common application is nucleoside analogues.     2'-O-(2-Methoxyethyl)guanosine CAS:473278-54-5     Nucleoside drug mechanism A nucleoside analogue is a nucleoside whose structure has been artificially modified, and this modification is usually performed on pentoses. The bases corresponding to lamivudine, telbivudine and entecavir are cytosine, thymine and guanine, respectively, and the bases corresponding to adefovir and tenofovir are both adenine. The antiviral mechanism of nucleoside analogues is to block the replication of virus by inhibiting the activity of HBV DNA polymerase. Because of the high similarity between the nucleoside structure of the drug and the viral polymerase, they can competitively bind to the viral polymerase, thus reducing the enzyme activity and terminating the extension of the viral DNA chain.     Rational selection of drugs The guidelines for the prevention and treatment of hepatitis B developed by the American College of Hepatology, the European College of Hepatology and the Asia Pacific Society of Hepatology all put forward the concept of "first-line drugs", i.e., first-line drugs should be preferred in antiviral therapy, and the recommended first-line drugs are entecavir, tenofovir and pegylated interferon.   People should put safety and efficacy in the first place when choosing drugs, and be guided by guidelines, taking into account price, health insurance and accessibility of drugs. In terms of drug safety, the focus should be on side effects and teratogenicity. China has conducted quality consistency evaluation of approved generic drugs in batches according to the principle of consistent quality and efficacy with the original drug, which provides new help for our drug selection.     Antiviral therapy for chronic hepatitis B is the key to treatment, and nucleoside analogues are effective antiviral drugs. Please contact CHEMENU to get more products and the quote.  




    Chemenu, founded in 2009, provides a wide variety of organic compounds and offers exclusive development for advanced intermediates. We manufacture building blocks, intermediates and novel compounds.   Our goal is to support research projects for pharmaceutical and biotech companies, drug discovery centers, academic institutions and other research organizations worldwide.         Part of the Linkchem Group, Chemenu can also supply CRO, CMO, CDMO services for R&D, process and commercial production. We are proud to be a reliable partner for our clients all over the world.       On the occasion of New Year's Day 2022, our company held a grand annual meeting ceremony. The auditorium was beautifully decorated with flashing lights.               We held an award ceremony. Partners with outstanding achievements in 2021 were appreciated, including contribution awards and team awards, and we wished our employees to continue their efforts in the coming year.         At the end of the annual meeting, we had a talent show session. Singing, dancing, drama, everyone enjoyed having fun.         Chemenu will keep on going and do our best to research new products and serve our customers.    



  • What Are the Characters of Pesticide Intermediates?

    Intermediates are a very important fine chemical product, essentially a class of "semi-finished products", which are intermediate products for the production of certain products. It can save cost and is widely used in the synthesis of pharmaceuticals, pesticides, coatings, dyes and fragrances. In the pharmaceutical field, intermediates are an important link in the pharmaceutical industry chain, and today, CHENENU mainly talk about pesticide intermediates.   What is pesticide Pesticides are chemical synthetics or mixtures of one substance or several substances composed of biological or other natural substances and their preparations used to prevent, destroy or control agricultural, forest, disease, insect, grass and other pests and purposefully regulate the growth of plants and insects. Pyrazole substances are common here. Broadly speaking, pesticides are divided into crop protection pesticides and non-crop protection pesticides. Crop protection pesticides are mainly divided into herbicides, insecticides, fungicides and plant growth regulators, etc., which are mainly used for agricultural protection; non-crop protection pesticides mainly include rodenticides, insect repellents, sanitary mosquito supplies, etc.       Synthesis process The synthesis of pharmaceutical intermediates is generally carried out in the reactor, and the generated intermediates should be separated and purified, which is usually achieved through extraction technology. And chloroform extraction of pesticide intermediates is a common operating unit in chemical enterprises, and the traditional operating process generally uses distillation tower operation. This operation process is complex, with low extraction efficiency and high power consumption, so most enterprises began to make technical changes to choose a more efficient process for the operation. Solvent extraction method began to become the main operating unit of the extraction section in the chemical industry. This method is simple to operate, with high extraction efficiency and cheap and easy to obtain extraction agent, while the extraction agent can be recycled, effectively saving the comprehensive input cost.   4-Methyl-L-phenylalanine     The role of intermediates The pesticide industry is at the end of the chemical industry chain and belongs to the fine chemical industry. Under the contradiction of global population growth and decreasing arable land, the massive use of pesticides to increase the yield per unit area is an important way to solve the food problem. Different insecticides require different intermediates in the production process. The products resulting from the processing of agricultural raw materials are also intermediates, which can be understood as synergists, also known as organic intermediates. Initially, they are intermediates produced in the process of synthesizing chemical products such as fragrances, dyes, resins, drugs, plasticizers, rubber accelerators, etc. from coal tar or petroleum products.       Pesticides are important production materials in agricultural production and play an extremely important role in controlling pests, diseases and weeds, stabilizing and improving crop yields. We provide custom synthesis/manufacturing including multi-step organic synthesis, process development, pilot and commercial manufacturing, and CMC services. Please contact us if you need to buy them.    



  • The CDMO Demand behind the ADC Drug Boom

    IUPAC Name:2,5-dioxopyrrolidin-1-yl 2-iodoacetate



  • The Importance of Steroid Hormones in the API Industry

    Since the 1990s, the sales of steroid hormone drugs in the international market have been increasing at a rate of 10%~15% per year. At present, steroid drugs are the second largest class of chemical drugs after antibiotics, and China has taken the development of new resources of steroid hormone drugs as one of the directions and priorities of the recent development of the pharmaceutical industry. The export of hormone APIs and intermediates has become an important variety of Chinese APIs to the world.