Nucléosides et Nucléotides

<p>Valaciclovir Related Compound E is a white crystalline powder that has an appearance similar to acyclovir, with a melting point of 164-167°C. It is soluble in water and methanol. The compound is used as a medicament and also acts as an intermediate for the synthesis of other pharmaceutical products. Valaciclovir Related Compound E can be synthesized from valaciclovir by reacting it with ethyl chloroformate, followed by recrystallization from pyridine and chloroform. This process produces the desired product in high purity under good yield. Valaciclovir Related Compound E is a white crystalline powder that has an appearance similar to acyclovir, with a melting point of 164-167°C. It is soluble in water and methanol. The compound is used as a medicament and also acts as an intermediate for the synthesis of other pharmaceutical products. Valac</p>

<p>cis 5-Fluoro-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]-2,4(1H,3H)-pyrimidinedione is a drug product that has been custom synthesized for use as an analytical reference material and an impurity standard. It is a synthetic compound and has not been approved for any medicinal purposes. The pharmacopoeia it falls under is the United States Pharmacopeia (USP) and the European Pharmacopoeia (EP). cis 5-Fluoro-1-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]-2,4(1H,3H)-pyrimidinedione is used to determine the purity of active pharmaceutical ingredients in finished drug products. It can also be used as a research and development tool to study metabolism studies of natural compounds.</p>

<p>Levovirin is an antiviral agent that belongs to the class of ribonucleotide reductase inhibitors. It is a potent inhibitor of hepatitis C virus replication and has been shown to be active against HIV in vitro. Levovirin acts as a competitive inhibitor of the NS3 protease, which is responsible for processing viral proteins. This inhibition prevents the production of new virus particles and the spread of infection. Levovirin also has immunomodulatory effects, which may provide therapeutic benefits in autoimmune diseases such as rheumatoid arthritis or Crohn's disease.</p>

<p>1-b-D-Ribofuranosyl-1,2,4-triazole-3-carboxylic acid (1bRT) is an amide that inhibits the growth of viruses by inhibiting the viral enzyme thiosemicarbazide. It has been shown to be active against specific viruses such as HIV and retroviruses. 1bRT is used to treat lung diseases caused by viruses, including bronchiolitis, pneumonia, and pulmonary fibrosis. It also has antibacterial properties. Studies have shown that 1bRT reduces the number of bacteria in body fluids and helps to prevent respiratory infections and other bacterial infections in people with weakened immune systems due to AIDS or cancer treatment.</p>

<p>Dapagliflozin impurity 2 is an impurity of dapagliflozin. It has been shown to be metabolized by erythrocytes and to be excreted in urine. Dapagliflozin impurity 2 has been identified in the USP Reference Standard for Dapagliflozin Impurity 2 (1830346-16-1). This material is available for custom synthesis, research, and development.</p>

<p>Remdesivir impurity 14 is a research and development product that belongs to the class of drugs. It is a synthetic metabolite with high purity. Remdesivir impurity 14 meets the pharmacopoeia standard for drug products and drug development. It has been synthesized to be used as an analytical standard for HPLC analysis of remdesivir. This product also has niche applications in metabolism studies, because it is a natural metabolite with its own metabolic pathway.</p>

<p>Sofosbuvir impurity 3 is a research and development, impurity standard, custom synthesis, drug product, synthetic, high purity, pharmacopoeia, drug development and analytical. Sofosbuvir impurity 3 is a metabolite of sofosbuvir which has been studied in metabolism studies using HPLC. This compound has also been shown to inhibit the growth of some bacteria.</p>

<p>Remsesivir related compound 11 is a research and development chemical that is used as an analytical, drug development, or impurity standard. It is a high purity, pure substance that can be custom synthesized or natural. Remsesivir related compound 11 has been shown to be metabolized by cytochrome p450 enzymes and glutathione reductase and has shown pharmacopoeia activities. Remsesivir related compound 11 can also be used as a HPLC standard for the detection of metabolites in pharmaceutical products.</p>

<p>Triphenylmethanol (TPM) is an inhibitor of the enzyme alcohol dehydrogenase. It is synthesized by reacting p-hydroxybenzoic acid with a hydroxyl group in the presence of trifluoroacetic acid and potassium carbonate. The reaction solution was then analyzed by x-ray crystallography, revealing the molecular structure of TPM. TPM binds to the metal ion in a hydroxyl group, preventing alcohol dehydrogenase from oxidizing ethanol to acetaldehyde. This mechanism also explains why TPM inhibits other enzymes that use this same metal ion cofactor such as carboxypeptidase A and aminopeptidase P, which are involved in protein synthesis and degradation.</p>

<p>Ribavirin is an antiviral drug that inhibits the synthesis of RNA and DNA. It is used to treat human immunodeficiency virus (HIV) infection, hepatitis B, and influenza A. Ribavirin is a nucleoside analog that acts as an antimetabolite by inhibiting acid synthesis in the host cell and therefore blocking viral replication. Ribavirin has been shown to inhibit dna viruses like herpes simplex virus type 1 and 2, as well as RNA viruses like influenza A and respiratory syncytial virus. Ribavirin also binds to the ribonucleotide reductase enzyme, which is necessary for the production of deoxyribonucleotides from ribonucleotides during DNA synthesis, thereby interfering with DNA replication.</p>

<p>3'-Deoxy-3'-chlorothymidine is an antiviral compound that is synthesized by the on-line coupling of 2,4-dichlorobenzoyl chloride with 3,4-dideoxycytidine. This process is performed using a reversed-phase high performance liquid chromatography method. The product is purified using a reversed phase high performance liquid chromatography method which maximizes its purity and minimizes the presence of impurities. The sensitivity of this analytical method is determined by the organic solvent used (acetonitrile) and the type of chromatographic column material (reverse phase).</p>

<p>Acyclovir EP Impurity Q is a drug product that is used as the impurity standard for Acyclovir EP. It is a natural metabolite of acyclovir and may be found in the urine of patients taking this drug. Acyclovir EP Impurity Q has shown to have antiviral activity against herpes simplex virus type 1 and type 2. The structure of this compound has been determined by nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry.</p>

<p>1-(2-Deoxy-beta-D-xylofuranosyl)-5-methyluracil (1DXP) is a nucleoside that inhibits the enzyme UDP glucose pyrophosphorylase. This enzyme is involved in the synthesis of uridine nucleotides, which are required for RNA and DNA synthesis. 1DXP has been shown to be effective against hepatitis B virus and lymphocytic leukemia cells in vitro. The mechanism of action of 1DXP is not well understood, but it may be related to the inhibition of protein synthesis or cellular metabolism. It may also inhibit the enzyme amino transferase, which is important for the synthesis of aromatic amino acids such as phenylalanine and tyrosine.</p>

<p>Remdesivir impurity 1 is a drug product, analytical and Metabolism studies. It is a custom synthesis, Impurity standard, Synthetic and Drug development. Remdesivir impurity 1 is an API impurity that is a natural and has CAS No. 1355049-95-4. The HPLC standard of Remdesivir impurity 1 is high purity and pharmacopoeia.</p>

<p>4-Amino-1-[3,5-di-O-(4-chlorobenzoyl)-2-deoxy-α-D-ribofuranosyl]-1,3,5-triazin-2(1H)-one (4AAT) is an analytical chemical that is used for research and development purposes. 4AAT is a metabolite of the antibiotic ampicillin and has been identified as an impurity in the drug product. It can be synthesized from 2-(4'-chlorophenyl)benzaldehyde, 3,5'-di-O-(4'-chlorobenzoyl)-2',3'-dideoxyribose and sodium azide in a two step process with 98% purity. 4AATs are also found to be present in natural products such as honey or sugar cane juice.</p>

<p>Remdesivir is an antiviral drug that inhibits the viral enzyme, RNA-dependent RNA polymerase. Remdesivir is administered in combination with other antiviral drugs to treat HIV-1 infection. The analytical impurity 4 is a metabolite of remdesivir and has been identified as a potential impurity in the drug product. CAS No. 2096985-18-9 is the molecular weight of this impurity. This impurity can be found in the pharmacopoeia, custom synthesis, natural, or synthetic form.</p>

<p>Gemcitabine hydrochloride is an analog of the natural nucleoside cytidine. It is a chemotherapeutic drug that is used in the treatment of pancreatic, lung and breast cancer. Gemcitabine hydrochloride is metabolized to its active form by deamination of cytosine residues in DNA. This conversion is catalyzed by the enzyme cytidine deaminase. Gemcitabine hydrochloride has been shown to be effective against metastatic pancreatic cancer and advanced-stage non-small cell lung cancer, as well as early-stage breast cancer. Gemcitabine hydrochloride has also been shown to be effective against certain types of lymphoma and leukemia.</p>

<p>5'-O-Acetyl ribavirin is an impurity of ribavirin, a drug product that belongs to the group of antiviral drugs. It is used in the treatment of chronic hepatitis C and influenza. 5'-O-Acetyl ribavirin is found in natural products such as plants, honey, and wine. The CAS number for this impurity is 58151-87-4. This compound can be synthesized through custom synthesis or by using a high purity HPLC standard as an impurity standard.</p>

<p>Decitabine related compound A is an impurity that is found in the API, decitabine. It is an analytical standard for HPLC measurements and a reference material for impurity testing. It is also used as a pharmacopoeia standard for pharmacopoeias such as European Pharmacopoeia, USP, and Japanese Pharmacopoeia. Decitabine related compound A has been synthesized from natural sources such as plant-derived alkaloids and synthetically produced in the laboratory. CAS No. 1019659-87-0</p>

<p>Entecavir (1R,3R,4S) diastereomer is a synthetic compound and is an analytical standard for HPLC. This product is an impurity of the drug Entecavir. The impurity is characterized by a retention time of 17.8 minutes on HPLC and has been shown to be metabolized in vitro to 8-hydroxy-entecavir. The purity of this product is 98% with a CAS number of 1367369-78-5.</p>