Recent Development in Synthetic Strategies for Oseltamivir Phosphate

Recent developments in synthetic strategies toward an important anti‐influenza drug, oseltamivir phosphate, are discussed. The importance of the drug further increased after the influenza A (H1N1) pandemic in 2009 and the emergence of the highly virulent avian influenza H5N1, which might eventually acquire the ability to spread between humans. Currently, the drug is produced in an industrial process of 11 chemical steps starting from (–)‐shikimic acid, whose availability is limited due to the massive demand of the drug. Thus, many chemists have been working to develop alternative synthetic processes to produce this important drug starting from readily available materials using environmentally benign, operationally safe, and cost‐effective methods. Synthetic efforts made by each group of chemists are described in this review article. The development of novel synthetic methodologies and novel reactions has had a great impact on the efficient syntheses of functional molecules, such as drugs like oseltamivir phosphate.