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Towards the total synthesis of chondrochloren A: synthesis of the (Z)-enamide fragment.

ABSTRACT: The stereoselective synthesis of the (Z)-enamide fragment of chondrochloren (1) is described. A Buchwald-type coupling between amide 3 and (Z)-bromide 4 was used to generate the required fragment. The employed amide 3 comprising three chiral centers was obtained through a seven-step sequence starting from ᴅ-ribonic acid-1,4-lactone. The (Z)-vinyl bromide 4 is accessible in four steps from 4-hydroxybenzaldehyde. The pivotal cross coupling between both fragments was achieved after extensive experimentation with copper(I) iodide, K₂CO₃ and N,N'-dimethylethane-1,2-diamine.

SUBMITTER: Geldsetzer J

PROVIDER: S-EPMC7176928 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Towards the total synthesis of chondrochloren A: synthesis of the (Z)-enamide fragment.

Geldsetzer Jan J Kalesse Markus M

Beilstein journal of organic chemistry 20200414

The stereoselective synthesis of the (Z)-enamide fragment of chondrochloren (1) is described. A Buchwald-type coupling between amide 3 and (Z)-bromide 4 was used to generate the required fragment. The employed amide 3 comprising three chiral centers was obtained through a seven-step sequence starting from ᴅ-ribonic acid-1,4-lactone. The (Z)-vinyl bromide 4 is accessible in four steps from 4-hydroxybenzaldehyde. The pivotal cross coupling be ...[more]

PMID: 32362944

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