First Total Synthesis of Reassigned Echinosulfonic Acid D.

J Nat Prod

Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Kita-ku, Okayama 7008530, Japan.

Published: August 2022

Echinosulfonic acid D, a sponge metabolite whose structure was recently reassigned, was synthesized for the first time. The key step is the double indolization of dimethylbarbituric acid using the umpolung indole reagent, followed by a hydrolysis/decarboxylation/esterification sequence.

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http://dx.doi.org/10.1021/acs.jnatprod.2c00559DOI Listing

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First Total Synthesis of Reassigned Echinosulfonic Acid D.

J Nat Prod

August 2022

Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 1-1-1 Tsushima-naka, Kita-ku, Okayama 7008530, Japan.

Echinosulfonic acid D, a sponge metabolite whose structure was recently reassigned, was synthesized for the first time. The key step is the double indolization of dimethylbarbituric acid using the umpolung indole reagent, followed by a hydrolysis/decarboxylation/esterification sequence.

View Article and Find Full Text PDF

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