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Total Synthesis of Marine Alkaloids Motuporamines A and B via Ring Expansion of Cyclic ?-Keto Esters.

ABSTRACT: An expedient total synthesis of the title marine sponge alkaloids has been developed. The salient features of the synthesis are as follows: (i) preparation of the required 13- and 14-membered cyclic lactams with n + 4 ring-expansion strategy of cyclic ?-keto esters and (ii) functional group manipulation of the resulted keto ester lactams. This approach used easily accessible and inexpensive materials/reagents, thus providing a promising alternative to the existing preparations.

SUBMITTER: Song ZJ

PROVIDER: S-EPMC7808158 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Total Synthesis of Marine Alkaloids Motuporamines A and B via Ring Expansion of Cyclic β-Keto Esters.

Song Zi-Jie ZJ Meng Shu-Yu SY Wang Quan-Rui QR

ACS omega 20201222 1

An expedient total synthesis of the title marine sponge alkaloids has been developed. The salient features of the synthesis are as follows: (i) preparation of the required 13- and 14-membered cyclic lactams with <i>n</i> + 4 ring-expansion strategy of cyclic β-keto esters and (ii) functional group manipulation of the resulted keto ester lactams. This approach used easily accessible and inexpensive materials/reagents, thus providing a promising alternative to the existing preparations. ...[more]

PMID: 33458539

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