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Concise Synthesis of (+)-[¹³ C₄ ]-Anatoxin-a by Dynamic Kinetic Resolution of a Cyclic Iminium Ion.

ABSTRACT: An asymmetric total synthesis of [¹³ C₄ ]-anatoxin-a ([¹³ C₄ ]-1) has been developed from commercially available ethyl [¹³ C₄ ]-acetoacetate ([¹³ C₄ ]-15). The unique requirements associated with isotope incorporation inspired a new, robust, and highly scalable route, providing access to 0.110 g of this internal standard for use in the detection and precise quantification of anatoxin-a in freshwater. A highlight of the synthesis is a method that leverages a cyclic iminium ion racemization to achieve dynamic kinetic resolution in an enantioselective Morita-Baylis-Hillman (MBH) cyclization.

SUBMITTER: Lacharity JJ

PROVIDER: S-EPMC7409530 | biostudies-literature |

REPOSITORIES: biostudies-literature

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