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Enantioselective Total Synthesis of (+)-Monocerin, a Dihydroisocoumarin Derivative with Potent Antimalarial Properties.

ABSTRACT: We describe here the enantioselective synthesis of (+)-monocerin and its acetate derivative. The present synthesis features an efficient optically active synthesis of the ?-hydroxy-?-lactone derivative with high enantiomeric purity using Sharpless dihydroxylation as the key step. The synthesis also highlights a tandem Lewis acid-catalyzed, oxocarbenium ion-mediated diastereoselective syn-allylation reaction, and a methoxymethyl group promoted methylenation reaction. We investigated this reaction with a variety of Lewis acids. A selective CrO3-mediated oxidation of isochroman provided the corresponding lactone derivative. The synthesis is quite efficient and may be useful for the preparation of derivatives.

SUBMITTER: Ghosh AK

PROVIDER: S-EPMC6637414 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Enantioselective Total Synthesis of (+)-Monocerin, a Dihydroisocoumarin Derivative with Potent Antimalarial Properties.

Ghosh Arun K AK Lee Daniel S DS

The Journal of organic chemistry 20190429 10

We describe here the enantioselective synthesis of (+)-monocerin and its acetate derivative. The present synthesis features an efficient optically active synthesis of the β-hydroxy-γ-lactone derivative with high enantiomeric purity using Sharpless dihydroxylation as the key step. The synthesis also highlights a tandem Lewis acid-catalyzed, oxocarbenium ion-mediated diastereoselective syn-allylation reaction, and a methoxymethyl group promoted methylenation reaction. We investigated this reaction ...[more]

PMID: 31033292

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