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The 2\u2010azabicyclo[3.3.1]nonane framework was constructed by an unprecedented intramolecular cycloaddition of an eight\u2010membered cyclic nitrone. Using the steric bias of the bicyclic system, the quaternary carbon atom was constructed by a stereoselective aldol reaction. Further ring formations were performed by ring\u2010closing metathesis for the 13\u2010membered ring and an iodoamidation reaction for the pyrrolidine ring. The present synthesis has successfully provided an alternative route to the late\u2010stage intermediate of Overman\u2019s synthesis.<\/jats:p>","DOI":"10.1002\/anie.201501633","type":"journal-article","created":{"date-parts":[[2015,5,8]],"date-time":"2015-05-08T19:39:11Z","timestamp":1431113951000},"page":"7367-7370","source":"Crossref","is-referenced-by-count":25,"title":["Formal Synthesis of Sarain\u2005A: Intramolecular Cycloaddition of an Eight\u2010Membered Cyclic Nitrone to Construct the 2\u2010Azabicyclo[3.3.1]nonane Framework"],"prefix":"10.1002","volume":"54","author":[{"given":"Takuya","family":"Higo","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomoya","family":"Ukegawa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Satoshi","family":"Yokoshima","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tohru","family":"Fukuyama","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2015,5,8]]},"reference":[{"key":"e_1_2_2_1_2","doi-asserted-by":"publisher","DOI":"10.1002\/bscb.19860950907"},{"key":"e_1_2_2_1_3","first-page":"223","volume-title":"The Alkaloids, Vol. 73","author":"Delpech B.","year":"2014"},{"key":"e_1_2_2_2_2","first-page":"293","volume":"103","author":"Caprioli V.","year":"1992","journal-title":"Comp. 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