367252-59-3Relevant academic research and scientific papers
New, efficient synthesis of oseltamivir phosphate (Tamiflu) via enzymatic desymmetrization of a meso-1,3-cyclohexanedicarboxylic acid diester
Zutter, Ulrich,Iding, Hans,Spurr, Paul,Wirz, Beat
, p. 4895 - 4902 (2008/12/20)
(Chemical Equation Presented) A new, enantioselective synthesis of the influenza neuraminidase inhibitor prodrug oseltamivir phosphate 1 (Tamiflu) and its enantiomer ent-1 starting from cheap, commercially available 2,6-dimethoxyphenol 10 is described. The main features of this approach comprise the cis-hydrogenation of 5-(1-ethyl-propoxy)-4,6-dimethoxy-isophthalic acid diethyl ester (6a) and the desymmetrization of the resultant all-cis meso-diesters 7a and 7b, respectively. Enzymatic hydrolysis of the meso-diester 7b with pig liver esterase afforded the (S)-monoacid 8b, which was converted into cyclohexenol 17 via a Curtius degradation and a base-catalyzed decarboxylative elimination of the Boc-protected oxazolidinone 14. Introduction of the second amino function via SN2 substitution of the corresponding triflate 18 with NaN3 followed by azide reduction, N-acetylation, and Boc-deprotection gave oseltamivir phosphate 1 in a total of 10 steps and an overall yield of ～30%. The enantiomer ent-1 was similarly obtained via an enzymatic desymmetrization of meso-diester 7a with Aspergillus oryzae lipase, providing the (R)-monoacid ent-8a.
The synthetic development of the anti-influenza neuraminidase inhibitor oseltamivir phosphate (Tamiflu): A challenge for synthesis & process research
Abrecht, Stefan,Harrington, Peter,Iding, Hans,Karpf, Martin,Trussardi, Rene,Wirz, Beat,Zutter, Ulrich
, p. 621 - 629 (2007/10/03)
The evolution of the synthesis of oseltamivir phosphate (Tamiflu), used for the oral treatment and prevention of influenza virus infections (viral flu) is described. Oseltamivir phosphate is the ethyl ester prodrug of the corresponding acid, a potent and selective inhibitor of influenza neuraminidase. The discovery chemistry route and scalable routes used for kilo laboratory production as well as the technical access to oseltamivir phosphate from (-)-shikimic acid proceeding via a synthetically well-developed epoxide building block followed by azide transformations are reviewed. Synthesis and process research investigations towards azide-free conversions of the key epoxide building block to oseltamivir phosphate are discussed. The search for new routes to oseltamivir phosphate independent of shikimic acid including Diels-Alder approaches and transformations of aromatic rings employing a desymmetrization concept are presented in view of large-scale production requirements.
