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Expedient synthesis of ?,?-dimethyl-?-hydroxy carbonyl scaffolds via Evans' aldol reaction with a tertiary enolate.

ABSTRACT: An efficient synthetic methodology for 3-hydroxy-2,2-dimethyloctynoic acid (DHOYA) and several variants, which are increasingly common fragments encountered in bioactive marine cyanobacterial metabolites, was developed. These fragments were obtained in three steps via a tertiary aldol reaction utilizing an Evans' chiral auxiliary to afford the desired stereochemistry at the ?-hydroxy carbon. Thus far, this methodology has been successfully applied in determination of the absolute stereochemistry of eight cyanobacterial natural products, including the VGSC activator palymramide A.

SUBMITTER: Nunnery JK

PROVIDER: S-EPMC3100194 | biostudies-literature | 2011 Jun

REPOSITORIES: biostudies-literature

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Expedient synthesis of α,α-dimethyl-β-hydroxy carbonyl scaffolds via Evans' aldol reaction with a tertiary enolate.

Nunnery Joshawna K JK Suyama Takashi L TL Linington Roger G RG Gerwick William H WH

Tetrahedron letters 20110601 23

An efficient synthetic methodology for 3-hydroxy-2,2-dimethyloctynoic acid (DHOYA) and several variants, which are increasingly common fragments encountered in bioactive marine cyanobacterial metabolites, was developed. These fragments were obtained in three steps via a tertiary aldol reaction utilizing an Evans' chiral auxiliary to afford the desired stereochemistry at the β-hydroxy carbon. Thus far, this methodology has been successfully applied in determination of the absolute stereochemistry ...[more]

PMID: 21617761

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