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Studies toward the Total Synthesis of Parvifolals A/B: An Intramolecular o-Quinone Methide [4 + 2]-Cycloaddition To Construct the Central Tetracyclic Core.

ABSTRACT: Two different approaches funded upon the intramolecular [4 + 2]-cycloaddition of in situ generated o-quinone methides have been explored to construct the central tetracyclic core of parvifolals A/B. At the outset, a cross-pinacol coupling of 2-formyl tri-O-methyl resveratrol with 4-methoxysalicylaldehyde followed by acid treatment was found to provide the desired tetracyclic core with an internal olefin. The requisite pendant aryl group has been introduced by a Pd-catalyzed direct coupling of corresponding diazonium salt.

SUBMITTER: Paymode DJ

PROVIDER: S-EPMC6648467 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Studies toward the Total Synthesis of Parvifolals A/B: An Intramolecular o-Quinone Methide [4 + 2]-Cycloaddition To Construct the Central Tetracyclic Core.

Paymode Dinesh J DJ Ramana Chepuri V CV

ACS omega 20190110 1

Two different approaches funded upon the intramolecular [4 + 2]-cycloaddition of in situ generated o-quinone methides have been explored to construct the central tetracyclic core of parvifolals A/B. At the outset, a cross-pinacol coupling of 2-formyl tri-O-methyl resveratrol with 4-methoxysalicylaldehyde followed by acid treatment was found to provide the desired tetracyclic core with an internal olefin. The requisite pendant aryl group has been introduced by a Pd-catalyzed direct ...[more]

PMID: 31459360

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