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Asymmetric synthesis of four diastereomers of 3-hydroxy-2,4,6-trimethylheptanoic acid: proof of configurational assignment.

ABSTRACT: Four unique diastereomers of 3-hydroxy-2,4,6-trimethylheptanoic acid--(2R,3R,4R), (2S,3R,4R), (2S,3R,4S), and (2R,3R,4S)--the fatty acid component of callipeltin A and D, have been synthesized from commercially available (+)- and (-)-pseudoephedrine propionamide in 6 steps and 59% average overall yield. Comparison of the 1H and 13C NMR and optical rotation data of the resulting isomers with the natural fragment unambiguously verifies the configurational assignment of the natural isomer as (2R,3R,4R).

SUBMITTER: Turk JA

PROVIDER: S-EPMC1487186 | biostudies-literature | 2003 Oct

REPOSITORIES: biostudies-literature

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Asymmetric synthesis of four diastereomers of 3-hydroxy-2,4,6-trimethylheptanoic acid: proof of configurational assignment.

Turk Jeffrey A JA Visbal Gonzalo S GS Lipton Mark A MA

The Journal of organic chemistry 20031001 20

Four unique diastereomers of 3-hydroxy-2,4,6-trimethylheptanoic acid--(2R,3R,4R), (2S,3R,4R), (2S,3R,4S), and (2R,3R,4S)--the fatty acid component of callipeltin A and D, have been synthesized from commercially available (+)- and (-)-pseudoephedrine propionamide in 6 steps and 59% average overall yield. Comparison of the 1H and 13C NMR and optical rotation data of the resulting isomers with the natural fragment unambiguously verifies the configurational assignment of the natural isomer as (2R,3R ...[more]

PMID: 14510564

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