Antivirals

<p>Saquinavir is a HIV protease inhibitor drug that is used with other antiretroviral drugs for the treatment of HIV-1. As this drug prevents HIV protease activity, it prevents the proteolysis of the Gag polyprotein and thus results in non-infectious virus particles.</p>

<p>Anti-viral; HIV integrase inhibitor</p>

<p>Valacyclovir is a guanine nucleoside antiviral drug that is used to treat herpes exacerbations. This drug inhibits DNA polymerase and prevents viral DNA synthesis. Valacyclovir is the L-valine ester of acyclovir.</p>

<p>HIV-1 integrase inhibitor; inhibits DNA strand transfer</p>

<p>Emtricitabine is an antiviral drug that is used to treat chronic viral hepatitis, which is caused by the hepatitis B and C viruses. The drug blocks the activity of reverse transcriptase, which is an enzyme necessary for the replication of viral RNA in the body. Emtricitabine has been shown to be effective against acute hepatitis B virus infection and chronic hepatitis B virus infection with or without cirrhosis. It also has been shown to be effective against chronic hepatitis C virus infection with or without cirrhosis.</p>

<p>Tenofovir diphosphate triethylamine (mixture of diastereomers) is an antiviral compound, which is a synthetic chemical product derived from the parent compound, tenofovir. This formulation includes a mixture of diastereomers to enhance its solubility and bioavailability. The compound primarily functions as a nucleotide reverse transcriptase inhibitor (NRTI). It targets viral reverse transcriptase enzymes, inhibiting DNA synthesis and subsequent viral replication by causing premature chain termination.</p>

<p>Cytarabine is also known as cytosine arabinoside (ara-C) and is a chemotherapy drug that works by inhibiting DNA synthesis. It acts as a nucleoside analogue, which is incorporated into the growing DNA chain during replication. Cytarabine combines a cytosine base with an arabinose sugar (1β-arabinofuranosylcytosine) and is an analog for human deoxycytosine. Cytarabine interferes with DNA synthesis as it is rapidly converted to cytosine arabinoside triphosphate, damaging DNA when cells are in the synthesis phase (S phase). Tumor cells which are highly mitotic and growing rapidly are therefore preferably targeted. Cytarabine also inhibits nucleotide reductase enzymes as well as nuclear polymerases, leading to interruption and inhibition of synthesis, strand breaks and cell death.</p>

<p>Emtricitabine is a nucleoside analog that is an antiviral drug used to treat HIV/AIDS. It is a synthetic nucleoside analog of cytidine, in which the 3' phosphate and 5' hydroxyl groups have been replaced with a fluorine atom and a methoxy group, respectively. Emtricitabine has been shown to inhibit the synthesis of viral DNA by competing for incorporation into the viral DNA strand during the elongation phase of viral replication. Emtricitabine also has anticancer activity, but no other known therapeutic uses.</p>

<p>Galidesivir dihydrochloride is an investigational antiviral drug, which is a synthetic nucleoside analogue with broad-spectrum activity. It is derived from a modified adenosine analog structure, targeting viral RNA-dependent RNA polymerases. Galidesivir functions through the incorporation into viral RNA, leading to premature termination of RNA synthesis, effectively inhibiting viral replication. This mechanism aligns with its utility in combating various RNA viruses.</p>

<p>Etravirine is a non-nucleoside reverse transcriptase inhibitor (NNRTI) medication used in the treatment of human immunodeficiency virus (HIV) infections. It works by blocking reverse transcriptase, an enzyme essential for replication of the virus, thereby preventing the virus from multiplying and spreading. Etravirine is often used in combination with other antiretroviral drugs to effectively treat HIV/AIDS. It is commonly prescribed for patients with virus strains that are resistant to other NNRTI medications due to mutations that confer resistance- mutations K103N and Y181C. Etravirine is a diarylpyrimidine (DAPY) and has conformational isomerism meaning that it binds reverse transcriptase in an fleible manner, under multiple conformations. The impact of specific point mutations in the virus is therefore lessened.</p>

<p>Applications (S)-Isopropyl 2-(((R)-(((2R,3R,4R,5R)-3-((tert-Butyldimethylsilyl)oxy)-5-(2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)-4-fluoro-4-methyltetrahydrofuran-2-yl)methoxy)(phenoxy)phosphoryl)amino)propanoate is an intermediate in the synthesis of Sofosbuvir (R)-Phosphate (S675615), which 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>Applications 2-Hydroxy-2-methylpropanethioamide is an thioamide compound integrated as an constituent in the synthesis of Ritonavir (R535000) and its derivatives.<br></p>

<p>Applications 1-[2-Deoxy-3,5-O-[1,1,3,3-tetrakis(1-methylethyl)-1,3-disiloxanediyl]-β-D-erythro-pentofuranosyl]-1H-1,2,4-triazole-3-carboxamide is an intermediate in the synthesis of 2’-Deoxyribavirin-5’-triphosphate (D2149940) Triethylamine Salt, a potential new inhibitor for HIV-1 replication.<br>References Vivet-Boudou, V., et al.: Nucleos. Nucleot. Nucl., 26, 743 (2007);<br></p>

<p>Applications (S)-2-(3-((2-(2-Hydroxypropan-2-yl)thiazol-4-yl)methyl)-3-methylureido)-3-methylbutanoic Acid is an intermediate in the synthesis of Ritonavir (R535000) derivatives.<br></p>

<p>Applications 1-[2-O-(Phenoxythioxomethyl)-3,5-O-[1,1,3,3-tetrakis(1-methylethyl)-1,3-disiloxanediyl]-β-D-ribofuranosyl]-1H-1,2,4-triazole-3-carboxamide is an intermediate in the synthesis of 2’-Deoxyribavirin-5’-triphosphate (D2149940) Triethylamine Salt, a potential new inhibitor for HIV-1 replication.<br>References Vivet-Boudou, V., et al.: Nucleos. Nucleot. Nucl., 26, 743 (2007);<br></p>

<p>Applications Used in the synthesis of enantioselective synthesis of carbocyclic ribavirin, its analogs and other antiviral agents.<br>References Kuang, R. et al.; Tetrahedron Lett. 41, 9575 (2000)<br></p>

<p>Applications Intermediate in the preparation of Ribavirin.<br></p>

<p>Applications Intermediate in the preparation of α-Ribavirin.<br></p>

<p>Applications (S)-2-(3-((2-(2-Hydroxypropan-2-yl)thiazol-4-yl)methyl)-3-methylureido)-3-methylbutanoic Acid Methyl Ester is an intermediate in the synthesis of Ritonavir (R535000) derivatives.<br></p>