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Enantioselective Total Synthesis of (-)-Deoxoapodine.

ABSTRACT: The first enantioselective total synthesis of (-)-deoxoapodine is described. Our synthesis of this hexacyclic aspidosperma alkaloid includes an efficient molybdenum-catalyzed enantioselective ring-closing metathesis reaction for the desymmetrization of an advanced intermediate that introduces the C5-quaternary stereocenter. After C21-oxygenation, the pentacyclic core was accessed by electrophilic C19-amide activation and transannular spirocyclization. A biogenetically inspired dehydrative C6-etherification reaction proved highly effective to secure the F-ring and the fourth contiguous stereocenter of (-)-deoxoapodine with complete stereochemical control.

SUBMITTER: Kang T

PROVIDER: S-EPMC5647245 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Enantioselective Total Synthesis of (-)-Deoxoapodine.

Kang Taek T White Kolby L KL Mann Tyler J TJ Hoveyda Amir H AH Movassaghi Mohammad M

Angewandte Chemie (International ed. in English) 20170927 44

The first enantioselective total synthesis of (-)-deoxoapodine is described. Our synthesis of this hexacyclic aspidosperma alkaloid includes an efficient molybdenum-catalyzed enantioselective ring-closing metathesis reaction for the desymmetrization of an advanced intermediate that introduces the C5-quaternary stereocenter. After C21-oxygenation, the pentacyclic core was accessed by electrophilic C19-amide activation and transannular spirocyclization. A biogenetically inspired dehydrative C6-eth ...[more]

PMID: 28862815

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