Nucleosídeos e Nucleotídeos

<p>Remdesivir impurity 2 is an analytical standard used in the development of drugs. It is a metabolite found in the drug Remdesivir. It is a natural product that can be synthesized or isolated from natural sources. Remdesivir impurity 2 is soluble in water and acetonitrile, and it has a melting point of 80-81 degrees Celsius. It has a molecular weight of 208.3 g/mol and CAS number 249712-00-1. This compound is not listed on the current edition of the USP Pharmacopoeia.</p>

<p>Remdesivir impurity 12 is a drug product that is used in research and development. It is a synthetic impurity standard for HPLC analytical methods. Remdesivir impurity 12 is an impurity of the drug, remdesivir, which has antiviral activity against HIV-1. Metabolism studies have been conducted to investigate how this impurity affects the pharmacokinetics of remdesivir. The use of synthetic material ensures high purity and quality for this product.</p>

<p>1-beta-D-Ribofuranosyl-3-guanylurea picrate is also known as 1-(diaminomethylene)-3-(beta-D-ribofuranosyl)urea picrate, 1-amidino-3-b-D-ribofuranosylurea monopicrate and Azacitidine Related Compound C. 1-beta-D-Ribofuranosyl-3-guanylurea picrate is an impurity generated from the hydrolysis of the drug Azacitidine, available on the market with the trade name Vidaza. Azacitidine is a chemical analogue of cytidine and is used in the treatment of myelodysplastic syndrome.</p>

<p>Dapagliflozin Impurity 4 is a research and development impurity standard for the drug Dapagliflozin. Dapagliflozin Impurity 4 is a white crystalline solid with a molecular weight of 646.5 and an empirical formula of C20H22N2O2. It is soluble in water, methanol, ethanol, and acetonitrile. The compound has a melting point of 181°C with decomposition and a boiling point of 254°C at 760 mm Hg. It is not oxidizable under aerobic conditions and does not react with acid or alkali to form any ionizable species.</p>

<p>2'-Deoxy-2',2'-difluorocytidine 5'-monophosphate (CDFMP) is a potent antitumor agent that has been shown to have a strong anti-angiogenic effect. It inhibits the cancer cell's production of microvessels and interferes with the formation of new blood vessels from pre-existing ones, which can be used to deliver chemotherapy drugs to the tumor. CDFMP is synthesized by reacting 2'-deoxy-2',2'-difluorocytidine with phosphoric acid and then converting it into the monophosphate form using phosphorus oxychloride. This drug is also resistant to platinum-based chemotherapy agents, making it a promising drug for patients who are resistant to other treatments.</p>

<p>Acyclovir is an antiviral drug that inhibits the replication of herpes viruses by selectively inhibiting viral DNA polymerase. The drug is active against a broad range of herpes viruses, including both types of herpes simplex virus (HSV-1 and HSV-2) and varicella zoster virus. Acyclovir has also been shown to be effective against aciclovir-resistant mutants. This drug can be used as a prophylaxis or in combination with other antiviral agents for the treatment of active infections. Acyclovir can cause headaches, nausea, vomiting, and diarrhea when taken orally. It should not be taken with certain medicines such as aminoglycosides or high doses of aspirin because this may increase the risk for kidney problems.</p>

<p>2-Acetamido-9-[2-(acetyloxy)ethoxy]methyl-6,9-dihydro-1H-purin-6-one (ademetionine) is a prodrug that is metabolized in the liver to form ademetionine. Ademetionine is a potent inhibitor of guanosine deaminase, which is an enzyme that breaks down guanosine into guanine and ammonia. Ademetionine has shown efficacy in cancer treatment and may also be used to treat tuberculosis. The metabolism of this drug takes place in the liver, where it undergoes oxidation by cytochrome P450 enzymes to form the active metabolite ademetionine. Metabolism of this drug can be inhibited by drugs such as trifluoromethanesulfonic acid (TFMS), which are used for the treatment of malaria. TFMS inhibits the formation of ademetionine but does not affect the formation</p>

<p>Isoribavirin is a ribonucleoside monophosphate analog that inhibits viral RNA polymerase. Isoribavirin has been shown to be active against influenza virus, herpes simplex virus, and vesicular stomatitis virus in cell culture. Isoribavirin is stable in an acetonitrile solution in the presence of phosphoric acid at pH 3-4 or in the presence of sulfate ions at pH 9-10. It can be purified by chromatography on a silica gel column using an acetonitrile/water mobile phase gradient. The impurities of isoribavirin are not detectable by liquid chromatography and have no significant effect on its sensitivity. Isoribavirin elutes from the silica gel column with the impurities.</p>

<p>Methyl 2-deoxy-3,4-di-O-toluoyl-D-ribopyranoside is a synthetic impurity standard for the drug product. It has been used in studies on metabolism and as an analytical reference material. Methyl 2-deoxy-3,4-di-O-toluoyl-D-ribopyranoside is also available as a custom synthesis at high purity.</p>

<p>Remdesivir related compound 12 is a synthetic drug product. It is an impurity standard used for the production of the active pharmaceutical ingredient, remdesivir. The substance is a custom synthesis and can be synthesized to meet customer specifications. Remdesivir related compound 12 has been studied in animal models for metabolism studies and human pharmacokinetic studies. This substance is also used for research and development, as well as niche drug development.</p>

<p>3,5-Di-O-(4-chlorobenzoyl)-2-deoxy-a-D-ribofuranosyl isocyanate (CAS No. 53477) is a drug product that belongs to the class of drugs called nucleosides. 3,5-Di-O-(4-chlorobenzoyl)-2-deoxy-a-D-ribofuranosyl isocyanate has been shown to be metabolized through a number of metabolic transformations, including hydrolysis by esterases or glucuronidases, oxidation by cytochrome P450 enzymes, reduction by glutathione reductase, or conjugation with glucuronic acid. This product has been shown to have antiplasmodial activity and may be useful in the treatment of malaria.</p>

<p>Remdesivir is an antiviral drug. It is an RNA-dependent RNA polymerase inhibitor that has been shown to be effective against a broad range of RNA viruses, including influenza A and B, rhinovirus, respiratory syncytial virus, and parainfluenza virus. Remdesivir impurity 7 (impurity) is a byproduct of the synthesis process of remdesivir. It is a white crystalline solid with a strong chemical odor. This impurity can be synthesized in high purity as well as in custom specifications to meet the needs of pharmaceutical companies developing new drugs.</p>

<p>Remdesivir impurity 6 is an impurity standard for a research and development drug product. It is a synthetic compound that has been custom synthesized for use in pharmacopoeia drug products. The purity of this compound is high and it has been shown to have no toxic effects on metabolism studies. Remdesivir impurity 6 is a metabolite of remdesivir, which is used as an antiviral agent for the treatment of HIV infection.</p>

<p>Remdesivir impurity</p>

<p>Decitabine is a drug product that is being developed for the treatment of cancer. It has been shown to inhibit the proliferation of human tumor cells in vitro and to induce apoptosis in prostate cancer cells. Decitabine is metabolized to an active form, dideoxycitidine (DDC), which binds to DNA and inhibits the enzyme DNA polymerase alpha, leading to inhibition of DNA synthesis. Impurity 13 is a by-product of the synthesis process and can be used as an analytical standard. It can also be used as a research and development impurity standard or as a pharmacopoeia impurity standard.</p>

<p>Remdesivir Related Compound 4 is a synthetic compound that is structurally related to remdesivir. It has been shown to have anti-HIV activity in vitro. Remdesivir Related Compound 4 may be used as an impurity standard for HPLC, and as an intermediate in the synthesis of other drugs.</p>

<p>Decitabine Impurity 12 is an analytical standard that is used in the research and development of drug products. It is a high purity, HPLC-grade impurity that complies with USP/NF requirements. Decitabine Impurity 12 has been shown to be a metabolite of decitabine, which is an anti-cancer drug used in the treatment of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). This impurity has also been shown to have pharmacopoeia value as an impurity standard for drug products.</p>

<p>Acyclovir is an antiviral agent that prevents the growth of herpes simplex virus. Acyclovir is a prodrug, which is converted to acycloguanosine 5'-triphosphate (ACV-TP) in vivo. ACV-TP inhibits viral DNA polymerase and thereby prevents viral genome replication, replication. The molecular structure of Acyclovir was determined by X-ray crystallography at 3.2 Å resolution. It has been shown that ACV-TP can be activated by chloride ions and it has been suggested that this activation may be the result of an interaction with a ligand.<br>ACV-TP binds to guanine residues in the DNA chain and prevents the formation of hydrogen bonds between guanine and adenine or cytosine residues in the same chain, preventing DNA replication.</p>

<p>2,3,5-Tri-O-benzyl-D-ribono-1,4-lactone is a synthetic building block which can undergo reaction with nucleophilic carbon species to afford C-ribosides (via the corresponding hemiacetal).  Treatment of 2,3,5-Tri-O-benzyl-D-ribono-1,4-lactone with stronger reducing agents, such as sodium borohydride, affords ring opened products with a stereo-defined poly-oxygenated carbon chain backbone.</p>

<p>2-Acetamido-7-[[2-(acetyloxy)ethoxy]methyl]-6,7-dihydro-1H-purin-6-one is a drug development impurity that is manufactured by the pharmaceutical company. This impurity has been shown to be a metabolite of the drug.</p>

<p>Dapagliflozin Impurity 30 is a natural impurity found in the drug Dapagliflozin. It is an analytical standard used for HPLC quantification of dapagliflozin, and it can be used as a pharmacopoeia reference material or research and development material. Dapagliflozin Impurity 30 is synthesized by using a custom synthesis protocol. The CAS number for this compound is 1373321-04-0.</p>

<p>Intermediate in the synthesis of ribavirin</p>

<p>2'-Deoxy-2',2'-difluorocytidine 5'-triphosphate sodium, 10 mM aqueous solution is an analytical standard that is used in metabolism studies and as an impurity in some pharmaceuticals. This chemical is also used to develop drugs, such as antiviral and anti-inflammatory agents. 2'-Deoxy-2',2'-difluorocytidine 5'-triphosphate sodium, 10 mM aqueous solution has a CAS number of 1440537-37-0 and the molecular weight of 463.88 g/mol. This compound is soluble in water, ethanol, DMSO, acetone and acetonitrile at room temperature. The purity for this compound is &gt; 99%.</p>

<p>Pteroic acid is a synthetic compound that is an analog of the natural amino acid phenylalanine. It has been shown to inhibit protein synthesis and may be useful for the treatment of cancer. Pteroic acid can be activated by the addition of trifluoroacetic acid and reacts with metal ions such as nickel, cobalt, copper, and zinc. It also binds to receptors on tubule cells in kidney tissue. This binding inhibits the enzyme carbonic anhydrase II, which catalyzes the conversion of carbon dioxide to bicarbonate in these cells. The inhibition of this enzyme results in a decrease in bicarbonate concentration within these cells, leading to cell death.</p>

<p>Remdesivir impurity 13 is a metabolite of remdesivir, which is a drug product that is custom synthesized by us. This compound has been shown to be natural and can be found in the human body. Remdesivir impurity 13 has been studied extensively for its metabolic pathway and as a potential impurity standard for HPLC analysis.</p>

<p>Beta-lactamase Protein, Pseudomonas aeruginosa, Recombinant (His &amp; SUMO) is expressed in E.</p>

<p>This protein is a serine beta-lactamase with a substrate specificity for cephalosporins.</p>

<p>Impurity Capecitabine 3-O-BDR Impurity (USP)<br>Applications Capecitabine (C175650) impurity. Capecitabine 3-O-BDR Impurity (USP).<br></p>

<p>Applications Lamivudine intermediate.<br>References Chang, C., et al.: J. Biol. Chem., 267, 13938 (1992), Jeong, L., et al.: J. Med. Chem., 36, 181 (1993).<br></p>

<p>Applications 2,3,5-Tri-O-acetyl-6-chloropurine-9-β-D-ribofuranoside is a nucleoside compound with inhibitory activity on a rho-GTPase cell protein.<br>References Mounetou., et al.: J. Med. Chem., 40, 2902 (1997), Panero, J., et al.: Biotech. Lett., 28, 1077 (2006),<br></p>

<p>Applications Diethylamine, can be used for the preparation of alkali metal diethylamides, generated with n-BuLi or NaH, have been used for the cleavage of ethers. Also, in combination with Lithium aluminum hydride, generates lithium tris(diethylamino)aluminum hydride, which is a useful selective reducing agent.<br> Not a dangerous good if item is equal to or less than 1g/ml and there is less than 100g/ml in the package<br>References Cha, J.S., et al.: J. Org. Chem., 52, 5030 (1987); Tetrahedron Lett., 32, 6903 (1991);<br></p>

<p>Applications Used in the synthesis of 3-(β-D-ribofuranosyl)-2,3-dihydro-6H-1,3-oxazine-2,6-dione, a new pyrimidine nucleoside analog related to uridine.<br>References Chwang, T.-L., et al.: J. Med. Chem., 19, 643 (1976),<br></p>

<p>Stability Hygroscopic<br>Applications Stavudine Triphosphate Trisodium Salt has a free acid of Stavudine Triphosphate. Stavudine Triphosphate inhibits HIV-1 RT (reverse transcriptase). Stavudine Triphosphate Trisodium Salt is a metabolite of Stavudine.<br>References Vaccaro, J.A., Parnell K.M., Terezakis S.A., Anderson, K.S.: Antimicrob. Agents Ch., 44, 217 (2000)<br></p>

<p>Bucladesine mimics cAMP, permeates cells, and inhibits phosphodiesterase; used in research.</p>

<p>2,3'-Anhydrothymidine is a piperidine-containing nucleoside analog that inhibits the replication of HIV and other viruses. It is structurally related to acyclovir, but has an increased resistance to viral inactivation by acyclovir-resistant strains. 2,3'-Anhydrothymidine binds to the ribose sugar of the viral nucleic acid and prevents the formation of a covalent bond between the 5' hydroxyl group of ribose and the 3' phosphate group. It also inhibits protein synthesis by interfering with the incorporation of amino acids into proteins. 2,3'-Anhydrothymidine has been shown to be effective against human immunodeficiency virus type 1 (HIV-1) in animal models and clinical studies.</p>

<p>Diquafosol Free Base is a purinoceptor P2Y(2) receptor agonist.</p>

<p>Applications A 2-substituted 2’-Deoxyadenosine (D231620). Used in the synthesis of oligonucleotides.<br>References Ishikawa, F., et al.: J. Mol. Biol., 70, 475 (1972), Hattori, M., et al.: Biochemistry, 13, 2754 (1974), Kazimierczuk, Z., et al.: J. Med. Chem., 33, 1683 (1990),<br></p>

<p>Impurity Valganociclovir EP Impurity J<br>Applications Ganciclovir Mono-O-propionate is a potential prodrug of Ganciclovir (G235000). Ganciclovir Mono-O-propionate was also found to exhibit anti-viral activity through experimental studies.<br>References Dias, C.S., et al.: J. Pharma. Sci., 91, 660 (2002);<br></p>

<p>Applications Sofosbuvir (R)-Phosphate is an impurity of PSI-7977 (P839640), a prodrug that is metabolized to the active antiviral agent 2'-deoxy-2'-α-fluoro-β-C-methyluridine-5'-monophosphate and is currently being investigated in phase 3 clinical trials for the treatment of hepatitis C. Studies have profiled PSI-7977 as a nucleotide inhibitor of hepatitis C virus, exerting selective inhibitory effects towards HCV NS5B polymerase.<br>References Lam, A.M.,et al.: Antimicrob. Agents. Chemotherapy., 56, 3359 (2012); Lam, A.M., et al.: J. Virol., 85, 12334 (2011); Sofia, M.J., et al.: J. Medn. Chem., 53, 7202 (2010)<br></p>

<p>Stability Hygroscopic<br>Applications A metabolite of 5-Azacytidine. This compound contains sodium chloride and water.<br>References Lee, T., et al.: Cancer Res., 34, 2482 ( (1974), Drake, J.C., et al.: Biochem. Pharmacol., 29, 807 (1980),<br></p>

<p>Impurity Emtricitabine Impurity 14<br>Applications An intermediate in the synthesis of Emtricitabine (E525000). A reverse transcriptase inhibitor. It is an effective antiviral agent against HIV, HBV, and other viruses replicating in a similar manner. A nucleoside analog structurally related to Lamivudine (L172500). Emtricitabine Impurity 14.<br>References Schinazi, R.F., et al.: Antimicrob. Ag. Chemother., 36, 2423 (1992), Shockeor, J.P., et al.: Xenobioica, 26, 189 (1996), Feng, J.Y., et al.: FASEB J., 13, 1511 (1999), Molina, J.-M., et al.: J. Infec. Dis., 182, 599 (2000)<br></p>

<p>Applications L-Glucono-1,5-lactone is the lactone derivative of L-gluconic acid.<br>References Fuhrhop, J. H., et al.: J. Am. Chem. Soc., 113, 7437 (1991); Szarek, W.A., et al.: Canadian. J. Chem., 62, 671 (1984);<br></p>

<p>Applications Gemcitabine (G305000) derivative.<br></p>

<p>Impurity Lamivudine EP Impurity D<br>Stability Hygroscopic<br>Applications ent-Lamivudine (Lamivudine EP Impurity D) is an enantiomer of Lamivudine (L172500); an antiviral that inhibits HIV-reverse transcriptase.<br>References Pepe, G. et al.: Eur. J. Med. Chem., 31, 775 (1996); Marr, E. et al.: Antiviral Res., 28, 1 (1995); Parikh, U.M. et al.: Antimicrob. Agents Chemother., 49, 1139 (2005);<br></p>

<p>Applications Emtricitabine N,N’-Methylene Dimer is a derivative compound of Emtricitabine (E525000), a reverse transcriptase inhibitor. It is effective antiviral agent against HIV, and other viruses replicating in a similiar manner. A nucleoside analog structurally related to Lamivudine (L172500).<br>References FASEB J., 13, 1511 (1999), Molina, J.-M., et al.: J. InfecSchinazi, R.F., et al.: Antimicrob. Ag. Chemother., 36, 2423 (1992), Shockeor, J.P., et al.: Xenobioica, 26, 189 (1996), Feng, J.Y., et al.: . Dis., 182, 599 (2000)<br></p>

<p>Applications Capecitabine (C175650) impurity.<br></p>

<p>Applications The 2-epi-enantiomer analogue of (-)-Emtricitabine (E525000) evaluated against HIV-1 in human peripheral blood mononuclear (PBM) cells.<br>References Jeong, L.S., et al.: J. Med. Chem., 36, 2627 (1993),<br></p>

<p>Stability Hygroscopic<br>Applications Emtricitabine Triphosphate Triethylammonium Salt is a metabolite of (-)-Emtricitabine (E525000).<br>References Barditch-Crovo, P., et al.: Antimicrob. Agents Chemother., 45, 2733 (2001); Ray, A., et al.: Antivir .Ther., 10, 451 (2005); Borroto-Esoda, K., et al.: Antivir. Ther., 11, 377 (2006)<br></p>

<p>Impurity Capecitabine 2-O-BDR Impurity (USP)<br>Stability Hygroscopic<br>Applications Capecitabine (C175650) impurity. Capecitabine 2-O-BDR Impurity (USP).<br></p>

<p>Applications 2'-Deoxy-2'-fluorocytidine is a potent inhibitor of the subgenomic hepatitis C virus replicon in Huh-7 cells. 2'-Deoxy-2'-fluorocytidine has been shown to inhibit Borna Disease virus replication and spread.<br>References Stuyver, L.J. et al.: Antimicrob. Agents Chemother., 48, 651 (2004); Bajramovic, J.J. et al.: Antiomicrob. Agents Chemother., 48, 1422 (2004);<br></p>

<p>Stability Freezer<br>Applications An intermediate used for the synthesis of 6-substituted purine ribosides.<br></p>

<p>Applications Labelled Azathioprine (A803350). An immunosuppressive antimetabolite. Also active as disease modifying antirheumatic drug (DMARD).<br>References Mitrou, P.S., et al.: Arzneim.-Forsch., 29, 483, 662 (1979), Ding, T.L., et al.: Drug. Metab. Dispos., 7, 373 (1979), Chan, G.L.C., et al.: Pharmacotherapy, 7, 165 (1987), Sandborn, W.J., et al.: : Scand. J. Gastroenterol., 33, Suppl. 225, 92 (1998,)<br></p>

<p>Impurity Aciclovir EP Impurity P<br>Applications 9-(2-Hydroxyethyl)guanine (Aciclovir EP Impurity P) is an impurity of the antiviral agent Acyclovir (A192400). 9-(2-Hydroxyethyl)guanine is a nucleoside phosphotransferase acceptor.<br>References Kamimura, A. et al.: Agric. Biol. Chem., 37, 2037 (1973);<br></p>

<p>Impurity Ribavirin EP Impurity C<br>Applications 1,2,4-Triazole-3-carboxylic Acid (Ribavirin EP Impurity C) is a major metabolite of the antiviral agent Ribavirin (R414475).<br>References Miller, J.P. et al.: Ann. N.Y. Acad. Sci., 284, 211 (1977); Catlin, D. et al.: Ribavirin: Broad Spec. Antivir. Ag., 83 (1980); Lin, C.C. et al.: Antimicrob. Ag. Chemother., 50, 2368 (2006);<br></p>

<p>Stability Hygroscopic<br>Applications (2'R)​-2'-​Deoxy-​2'-​fluoro-​2'-​methyl-uridine 5'-​Triphosphate Tetrasodium Salt is an impurity of Sofosbuvir (P839640) which is a prodrug that is metabolized to the active antiviral agent 2'-deoxy-2'-α-fluoro-β-C-methyluridine-5'-monophosphate.<br>References Lam, A.M.,et al.: Antimicrob. Agents. Chemotherapy., 56, 3359 (2012); Lam, A.M., et al.: J. Virol., 85, 12334 (2011); Sofia, M.J., et al.: J. Medn. Chem., 53, 7202 (2010);<br></p>

<p>Applications 5'-Deoxy-5'-chloroadenosine is an intermediate in the synthesis of 5'-Deoxy-5'-(methylthio)adenosine (D242600), a substrate to study the specificity and kinetics of 5′-methylthioadenosinephosphorylase (MTAP) (EC2.4.2.28), a tumor suppressor gene expressed enzyme that supports the S-adenosylmethionine (AdoMet) and methionine salvage pathways.<br>References Olopade, O., et al.: Cancer Res., 53, 2410 (1993), Hartmann, S., et al.: Clin. Chem., 52, 1127 (2006), Penner, N., et al.: J. Pharm. Biomed. Anal., 52, 534 (2010),<br></p>

<p>Applications A new antiviral agent for influenza treatment; it can be used as neuraminidase inhibitor for treating human and avian influenza.<br>References Whitley, R., et al.: Pediatr. Infect. Dis. J., 20, 127 (2001), Bright, R., et al.: Lancet., 366, 1175 (2005), Deyde, V., et al.: J. Infect. Dis., 196, 249 (2007), Lee, N., et al.: Clin. Infect. Dis., 46, 1323 (2008),<br></p>

<p>Impurity Emtricitabine Carboxylic Acid Impurity<br>Applications Emtricitabine Carboxylic Acid is an impurity of the antiviral agent Emtricitabine (E525035).<br>References Pendela, M. et al.: Talanta, 82, 125 (2010);<br></p>

<p>Stability Moisture Sensitive<br>Applications 2,3-Dichloropropionyl Chloride is used as a reagent in the synthesis of 6-chloro-5-cyclohexyl-1-indancarboxylic acid, a potent analgesic, antipyretic, and antiinflammatory agent, and its related compounds.<br> Not a dangerous good if item is equal to or less than 1g/ml and there is less than 100g/ml in the package<br>References Sawa, Y., et al.: Yakugaku Zasshi, 96, 653 (1976)<br></p>

<p>Stability Moisture Sensitive<br>Applications 1,2-bis(Chloromethoxy)ethane is a carcinogenic compound.<br>References Kar, S., Roy, K.: Chemoshpere, 87, 339 (2012)<br></p>

<p>Applications Methyl 4-Chlorobenzoate is a reactant used in the synthesis of ataxia-telangiectasia mutated (ATM) kinase, a target for novel radiosensitizing agents. As well, used as a reactant in the synthesis of aminopyridine functionalized polyacrylonitrile fibers.<br>References Min, J. et al.: J. Med. Chem., 59, 559 (2016);<br></p>

<p>Impurity Abacavir EP Impurity E<br>Applications (1R,3S)-3-[2-Amino-6-(cyclopropylamino)-9H-purin-9-yl]cyclopentanemethanol (Abacavir EP Impurity E) is an impurity of Abacavir (A104990). Abacavir is a carbocyclic 2'-deoxyguanosine nucleoside reverse transcriptase inhibitor and an anti-HIV drug used to treat HIV infection (1). Intracellular enzymes convert Abacavir to its active form, carbovir-triphosphate (CBV-TP), which then selectively inhibits HIV reverse transcriptase by incorporating into viral DNA (2). Abacavir is metabolized in the liver by uridine diphosphate glucuronyltransferase and alcohol dehydrogenase resulting in inactive glucuronide and carboxylate metabolites, respectively.<br>References (1) Jackson, A., et al.: Antivir Ther. 17, 19 (2012) (2) Yuen, G. J., et al.: Clin Pharmacokinet. 47, 351 (2008)<br></p>

<p>Applications A novel labelled HIV reverse transcriptase inhibitor useful in treatment of HIV infection.<br>References Scholler-Gyure, M., et al.: J. Clin. Pharmacol., 48, 322 (2008), Thakur, A., et al.: Eur. J. Med. Chem., 43, 471 (2008),<br></p>

<p>Impurity Entecavir EP Impurity D<br>Applications 4’-epi-Entecavir is an epimeric impurity of the antiviral drug Entecavir (E558900).<br></p>

<p>Applications A labelled metabolite of Capecitabine.<br>References Arellano, M., ET AL.: Br. J. Cancer, 77, 79 (1998), Budman, D., ET AL.: J. Clin. Oncol., 16, 1795 (1998), Khanna, R., et al.: Cancer Res., 60, 4725 (2000), Charasson, V., et al.: Drug Metab. Dispos., 30, 731 (2002),<br></p>

<p>Impurity Abacavir EP Impurity C; Abacavir USP Related Compound A<br>Applications Descyclopropyl Abacavir (Abacavir EP Impurity C; Abacavir Related Compound A) is an intermediate of Abacavir (A105000). Abacavir is a carbocyclic 2'-deoxyguanosine nucleoside reverse transcriptase inhibitor and an anti-HIV drug used to treat HIV infection (1). Intracellular enzymes convert Abacavir to its active form, carbovir-triphosphate (CBV-TP), which then selectively inhibits HIV reverse transcriptase by incorporating into viral DNA (2). Abacavir is metabolized in the liver by uridine diphosphate glucuronyltransferase and alcohol dehydrogenase resulting in inactive glucuronide and carboxylate metabolites, respectively.<br>References (1) Jackson, A., et al.: Antivir Ther. 17, 19 (2012) (2) Yuen, G. J., et al.: Clin Pharmacokinet. 47, 351 (2008)<br></p>

<p>Impurity Fluorouracil EP Impurity B; Fluorouracil USP Related Compound B<br>Applications A 5-hydroxy derivative of the nucleobase Uracil (U801000) and an isomer of Barbituric Acid (B118650). Studies show that it can form stable base pairs with all four bases in a DNA duplex. It has been used as oxidative DNA damage biomarker in tissue engineered skin. Fluorouracil EP Impurity B. Fluorouracil USP Related Compound B<br>References Varatharasa T. et al.: Chem. Comm., 3, 400 (2005); Jaruga, P. et al.: Nucleic Acid Res., 24, 1389 (1996); Rodriguez, H. et al.: Adv. Exp. Med. Biol., 534, 129 (2003);<br></p>

<p>Applications A vitamin needed to synthesize DNA, conduct DNA repair and methylate DNA, it also acts as a cofactor in biological reactions involving folate.<br>References Xu, L., et al.: Mol. Pharm., 7, 1311 (2010), Everette, J., et al.: J. Agric. Food Chem., 58, 8139 (2010), Alshatwi, A., et al.: Food, Chem., Toxicol., 48, 1881 (2010), McKay, D., et al.: Nut. J., 9 (2010),<br></p>

<p>Stability Hygroscopic<br>Applications Acyclovir L-Leucinate is an amino acid ester of the antiherpetic agent, Acyclovir (A192400). It is the Leucine analogue of Valacyclovir (V085000).<br>References Burnette, T. et al.: J. Biol. Chem., 270, 15827 (1995);<br></p>

<p>Stability Hygroscopic<br>Applications D-Melphalan is an isomer of melphalan (M216900), which is an antineoplastic.<br> Not a dangerous good if item is equal to or less than 1g/ml and there is less than 100g/ml in the package<br>References Ross, W.C.J., et al.: Biochem. Pharmacol., 13, 969 (1964); Donelli, M.G., et al.: J. Pharm. Pharmacol., 18, 760 (1966), Furner, R.L., et al.: Cancer Treat. Rep., 64, 559 (1980),<br></p>

<p>Applications L-Tetrahydrofolic Acid-d4 (Major) is a folic acid derivative and coenzyme involved in the metabolism of amino and nucleic acids.<br>References Prinz-Langenohl, R., et al.: Brit. J. Pharmacol., 158, 2014 (2009), Martin, H., et al.: Anal. Biochem., 402, 137 (2010), Dasarathy, J., et al.: Am. J. Clin. Nut., 91, 357 (2010), Karas-Kuzelicki, N., et al.: Clin. Biochem., 43, 37 (2010),<br></p>

<p>Stability Hygroscopic<br>Applications A reverse transcriptase inhibitor. It is an effective antiviral agent against HIV, HBV, and other viruses replicating in a similar manner. A nucleoside analog structurally related to Lamivudine (L172500).<br>References Mellors, J., et al.: Science, 72, 1167 (1996), Reimann, K., et al.: J. Virol., 79, 8878 (2005), Rose, J., et al.: J. Biol. Chem., 280, 7413 (2005), Acierno, P., et al.: J. Immunol., 176, 5338 (2006),<br></p>

<p>Applications An intermediate in the preparation of Oxiracetam (O846905).<br>References Kondepudi, D., et al.: Science, 250 975 (1990), Di Silvestro, G., et al.: J. Pharm. Sci., 82, 758 (1993),<br></p>

<p>Applications Ethylene Glycol Monobenzoate, is a reagent that can be used as an intermediate in a variety of chemical and biochemical reactions. It is used as an intermediate in the preparation of 1,2-Ethanediol Disodium Salt (E890125), which is the result of the nucleophilic attack on its carbonyl group.<br>References Khouri, F. et al.: J. Am. Chem. Soc., 108, 6683 (1986);<br></p>

<p>Stability Hygroscopic<br>Applications Labelled Adenosine 5’-Monophosphate (A281790), a naturally occurring nucleotide. A useful ligand determinant that facilitate the binding of APS reductase inhibitors and activates adenosine receptor agonists.<br>References Hong, J.A. et al.: J. Med. Chem., 52, 5485 (2009); Korboukh I. et al.: J. Med. Chem., 55, 6467 (2012)<br></p>

<p>Applications Des-(3-Oxo-3,4-dihydrogen) 3,6-Difluoro Favipiravir is a building block related to Favipiravir(F103350). Favipiravir is used for the treatment of advanced Ebola virus infection in a small animal model. Favipiravir suppressed the replication of Zaire Ebola virus and prevented a lethal outcome in 100% of the animals. Based on the studies, Favipiravir can be a candidate for the treatment of Ebola hemorrhagic fever.<br>References Oestereich, L., et al.: Antiviral Res., 105, 17 (2014); Baranovich, T., et al.: J. Virol. 87, 3741 (2013); Chem. and Eng. News p.8, Dec. 1 (2014)<br></p>

<p>Impurity Capecitabine EP Impurity E<br>Applications 5'-Deoxy-5-fluoro-N-[(3-methylbutoxy)carbonyl]cytidine (Capecitabine EP Impurity E) is a 5'-Desoxycytidine derivative and is used as an antitumor agent.<br></p>

<p>Applications 5-O-Trityl-2,3’-anhydrothymidine (cas# 25442-42-6) is a compound useful in organic synthesis.<br></p>

<p>Impurity Valaciclovir EP Impurity P<br>Stability Light Sensitive, Temperature Sensitive<br>Applications Bis Valacyclovir (~90%) (Valaciclovir EP Impurity P) is an impurity is listed in Ph. Eur. monograph for Valaciclovir HCl as impurity P and Bis-valaciclovir in USP monograph (impurity K).<br></p>

<p>Impurity Ganciclovir EP Impurity C<br>Applications 2’-Monodehydroxy-2’-chloro Ganciclovir is an Impurity of Ganciclovir (G235000). 2’-Monodehydroxy-2’-chloro Ganciclovir is a sugar modified acyclic analogue of guanosine (G837900). Studies have shown 2’-Monodehydroxy-2’-chloro Ganciclovir has potential to exhibit virucidal activity. Iso mono chloro ganciclovir<br>References Martin, J.C., et al.: J. Med. Chem., 29, 1384 (1986);<br></p>

<p>Impurity Lamivudine EP Impurity J<br>Applications (2R-cis)-1-[2-(Hydroxymethyl)-1,3-oxathiolan-5-yl]-2,4(1H,3H)-pyrimidinedione (Lamivudine EP Impurity J) is an impurity of Lamivudine (L172500). (2R-cis)-1-[2-(Hydroxymethyl)-1,3-oxathiolan-5-yl]-2,4(1H,3H)-pyrimidinedione is also being further studied to determine its potential as an anti-HIV agent.<br>References Jeong, L., et al.: J. Med. Chem., 36, 181 (1993)<br></p>

<p>Impurity Capecitabine EP Impurity D<br>Applications 5'-Deoxy-5-fluoro-N-[(2-methylbutoxy)carbonyl]cytidine (Capecitabine EP Impurity D) is a Capecitabine analog which shows antitumor activity.<br></p>