guanosine (standard)

Guanosine (Standard) is a standard preparation of guanosine, suitable for quantitative analysis, quality control, and biochemical experiments. Guanosine is a nucleotide composed of the purine base guanine, ribose, and phosphate groups, and is a constituent of RNA.

8-Hydroxy-2'-deoxyguanosine (Standard) is a reference standard for research and analysis in studies involving 8-Hydroxy-2'-deoxyguanosine. 8-Hydroxy-2'-deoxyguanosine (8-OHdG) is a good biomarker for risk assessment of various cancers and degenerative diseases.

Ribavirin-13C5is intended for use as an internal standard for the quantification of ribavirin by GC- or LC-MS. Ribavirin is an antiviral guanosine nucleoside analog.1,2Upon entry into cells, ribavirin is metabolized to an active triphosphate form that induces viral RNA chain termination and inhibits viral polymerases. It reduces replication in a panel of seven RNA and four DNA viruses in Vero cells (EC50s = 2-95 μg/ml).3Ribavirin also reduces replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Vero cells (EC50= 109.5 μM).4Aerosol administration of ribavirin (30 mg/kg) reduces mortality in a mouse model of influenza A infection.5Formulations containing ribavirin have been used in the treatment of respiratory syncytial virus (RSV), hepatitis C virus (HCV), and viral hemorrhagic fevers. 1.Gilbert, B.E., and Knight, V.Biochemistry and clinical applications of ribavirinAntimicrob. Agents Chemother.30(2)201-205(1986) 2.Gordon, C.J., Tchesnokov, E.P., Woolner, E., et al.Remdesivir is a direct-acting antiviral that inhibits RNA-dependent RNA polymerase from severe acute respiratory syndrome coronavirus 2 with high potencyJ. Biol. Chem.295(20)6785-6797(2020) 3.Kirsi, J.J., North, J.A., McKernan, P.A., et al.Broad-spectrum antiviral activity of 2-β-D-ribofuranosylselenazole-4-carboxamide, a new antiviral agentAntimicrob. Agents Chemother.24(3)353-361(1983) 4.Wang, M., Cao, R., Zhang, L., et al.Remdesivir and chloroquine effectively inhibit the recently emerged novel coronavirus (2019-nCoV) in vitroCell Res.30(3)269-271(2020) 5.Wilson, S.Z., Knight, V., Wyde, P.R., et al.Amantadine and ribavirin aerosol treatment of influenza A and B infection in miceAntimicrob. Agents Chemother.17(4)642-648(1980)

5'-Guanylic acid (Standard) is the standard substance of 5'-Guanylic acid, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. 5'-Guanylic acid (5'-guanosine monophosphate) is involved in several metabolic disorders, including AICA-ribosiduria pathway, adenosine deaminase deficiency,adenine phosphoribosyltransferase deficiency (aprt), and the 2-hydroxyglutric aciduria pathway.

5'-Guanylic acid disodium salt (Standard) is the standard substance of 5'-Guanylic acid disodium salt, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. 5'-Guanylic acid disodium salt (GMP-5) belongs to the class of organic compounds known as purine ribonucleoside monophosphates. In particular, L-Glutamic acid and guanosine monophosphate can be biosynthesized from xanthylic acid and L-glutamine; which is catalyzed by the enzyme GMP synthase [glutamine-hydrolyzing]. In addition, Guanosine triphosphate and guanosine monophosphate can be biosynthesized from diguanosine tetraphosphate; which is catalyzed by the enzyme bis(5'-nucleosyl)-tetraphosphatase [asymmetrical]. In humans, guanosine monophosphate is involved in the kanamycin action pathway, the telithromycin action pathway, the tobramycin action pathway, and the erythromycin action pathway. Guanosine monophosphate is also involved in several metabolic disorders, some of which include the AICA-ribosiduria pathway, adenosine deaminase deficiency, adenine phosphoribosyltransferase deficiency (aprt), and the 2-hydroxyglutric aciduria (D and L form) pathway. Outside of the human body, guanosine monophosphate can be found in a number of food items such as onion-family vegetables, millet, chinese water chestnut, and red rice. This makes guanosine monophosphate a potential biomarker for the consumption of these food products.

Ribavirin-13C5 (Standard) is the standard form of Ribavirin-13C5, suitable for quantitative analysis, quality control, and related research in biochemical experiments. Ribavirin-13C5 is intended to be used as an internal standard for the quantification of ribavirin by GC- or LC-MS. Ribavirin is an antiviral guanosine nucleoside analog. 1,2 Once it enters cells, ribavirin is metabolized into an active triphosphate form that causes viral RNA chain termination and inhibits viral polymerases. It reduces replication in a panel of seven RNA and four DNA viruses in Vero cells (EC50s = 2-95 μg/ml). 3 Ribavirin also reduces replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Vero cells (EC50 = 109.5 μM). 4 Aerosol administration of ribavirin (30 mg/kg) reduces mortality in a mouse model of influenza A infection.5Formulations containing ribavirin have been used in the treatment of respiratory syncytial virus (RSV), hepatitis C virus (HCV), and viral hemorrhagic fevers.

Sildenafil citrate (Standard) is the standard substance of Sildenafil citrate, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. Sildenafil citrate (UK-92480 citrate) , a cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5) Inhibitor, is used extensively for erectile dysfunction and less commonly for pulmonary hypertension.

Tadalafil (Standard) is the standard substance of Tadalafil, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. Tadalafil (IC-351) is a carboline-based compound with vasodilatory activity. Tadalafil selectively inhibits the cyclic guanosine monophosphate (cGMP)-specific type 5 phosphodiesterase- (PDE-5)-mediated degradation of cGMP, which is found in the smooth muscle of the corpus cavernosa and corpus spongiosum of the penis. Inhibition of cGMP degradation by tadalafil results in prolonged muscle relaxation, vasodilation, and blood engorgement of the corpus cavernosa, and, so, prolonged penile erection.

Vardenafil (Standard) is the standard substance of Vardenafil, and it is applicable for quantitative analysis, quality control, and related research in biochemical experiments. Vardenafil (Vivanza) is an oral therapy for the treatment of erectile dysfunction. It is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5). Penile erection is a hemodynamic process initiated by the relaxation of smooth muscle in the corpus cavernosum and its associated arterioles. During sexual stimulation, nitric oxide is released from nerve endings and endothelial cells in the corpus cavernosum. Nitric oxide activates the enzyme guanylate cyclase resulting in increased synthesis of cyclic guanosine monophosphate (cGMP) in the smooth muscle cells of the corpus cavernosum. The cGMP in turn triggers smooth muscle relaxation, allowing increased blood flow into the penis, resulting in erection. The tissue concentration of cGMP is regulated by both the rates of synthesis and degradation via phosphodiesterases (PDEs). The most abundant PDE in the human corpus cavernosum is the cGMPspecific phosphodiesterase type 5 (PDE5); therefore, the inhibition of PDE5 enhances erectile function by increasing the amount of cGMP.

Tadalafil-13C-D3 (Standard) is a reference standard of Tadalafil-13C-D3 intended for quantitative analysis, quality control, and related biochemical research applications. Tadalafil-13C-d3 the 13C and deuterated compound of Tadalafil. Tadalafil has a CAS number of 171596-29-5. Tadalafil is a carboline-based compound with vasodilatory activity. Tadalafil selectively inhibits the cyclic guanosine monophosphate (cGMP)-specific type 5 phosphodiesterase- (PDE-5)-mediated degradation of cGMP, which is found in the smooth muscle of the corpus cavernosa and corpus spongiosum of the penis. Inhibition of cGMP degradation by tadalafil results in prolonged muscle relaxation, vasodilation, and blood engorgement of the corpus cavernosa, and, so, prolonged penile erection.

Acyclovir-D4 (Standard) is a reference standard of Acyclovir-D4 intended for quantitative analysis, quality control, and related biochemical research applications. Acyclovir-d4 is a deuterated compound of Acyclovir. Acyclovir has a CAS number of 59277-89-3. Acyclovir is a synthetic analog of the purine nucleoside, guanosine, with potent antiviral activity against herpes simplex viruses type 1 and 2, varicella-zoster virus and other viruses of the herpesvirus family.