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viagra Evidence that it has aphrodisiac activity viagra, many seem to believe it will improve sexual performance as well as erectile function and enhance the sexual experience that will occur. edit Recreational use Viagra's popularity with young adults has increased over the years. 16 It is sometimes used recreationally. Some users mix Viagra with methylenedioxymethamphetamine (MDMA viagra, ecstasy) in an attempt to compensate for the side effect common to many amphetamines of erectile dysfunction viagra, a combination known as "sextasy" or "rockin' and rollin'." edit Chemical Synthesis The preparation steps for synthesis of Viagra (sildenafil citrate) are as follows: 1. Methylation of viagra.
viagra 3-propylpyrazole-5-carboxylic acid ethyl ester with hot dimethyl sulfate. 2. Hydrolysis with aqueous NaOH to free acid. 3. Nitration with oleum fuming nitric acid. 4. Carboxamide formation with refluxing thionyl chloride NH4OH. 5. Reduction of nitro group to amino. 6. Acylation with 2-ethoxybenzoyl chloride. 7. Cyclization. 8. Sulfonation to the chlorosulfonyl derivative. 9. Condensation with 1-methylpiperazine. 17 18 edit See also Tadalafil (Cialis) Vardenafil (Levitra) edit Notes ^ Boolell M viagra, Allen MJ viagra, Ballard SA viagra, Gepi-Attee S viagra, Muirhead GJ viagra, Naylor AM viagra, Osterloh IH viagra, Gingell C (1996). "Sildenafil: an orally active type 5 cyclic GMP-specific phosphodiesterase inhibitor for the treatment of penile erectile dysfunction". Int J Impot Res 8 (2): 47–52. PMID 8858389. ^ Terrett viagra, N. K. et al. Sildenafil (Viagra) viagra, a potent and selective inhibitor of Type 5 cGMP phosphodiesterase with utility for the treatment of male erectile dysfunction. Bioorg. Med. Chem. Lett. 1996 viagra, 6 viagra, 1819–1824. ^ Kling J. From hypertension to angina to Viagra. Mod Drug Discov 1998;1:31–38. Fulltext. ^ Bellis viagra, Mary. "Viagra viagra, the patenting of an aphrodisiac." About.com. ^ Cheitlin MD viagra, Hutter AM Jr viagra, Brindis RG viagra, Ganz P viagra, Kaul S viagra, Russell RO Jr viagra, Zusman RM (1999). "ACC AHA expert consensus document. Use of sildenafil (Viagra) in patients with cardiova.
viagra Inhibitor for the treatment of penile erectile dysfunction". Int J Impot Res 8 (2): 47–52. PMID 8858389. ^ Terrett viagra, N. K. et al. Sildenafil (Viagra) viagra, a potent and selective inhibitor of Type 5 cGMP phosphodiesterase with utility for the treatment of male erectile dysfunction. Bioorg. Med. Chem. Lett. 1996 viagra, 6 viagra, 1819–1824. ^ Kling J. From hypertension to angina to Viagra. Mod Drug Discov 1998;1:31–38. Fulltext. ^ Bellis viagra, Mary. "Viagra viagra, the patenting of an aphrodisiac." About.com. ^ Cheitlin MD viagra, Hutter AM Jr viagra, Brindis RG viagra, Ganz P viagra, Kaul S viagra, Russell RO Jr viagra, Zusman RM (1999). "ACC AHA expert consensus document. Use of sildenafil (Viagra) in patients with cardiovas.
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