Ester-imine condensations

Preparation of racemic intermediates for the synthesis of the carbapenem antibiotics PS-5 and PS-6

Deok-Chan Ha, D. J. Hart

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

The lithium enolates of ethyl butyrate (7) and ethyl isovalerate (19) react with N-p-methoxyphenylcinnamaldimine (8) in tetrahydrofuran (THF) - hexamethylphosphoric triamide (HMPA) to afford predominantly trans β-lactams 9 (67%) and 20 (78%), respectively. β-Lactam 9 was converted to PS-5 (5) intermediate 18 in 21% overall yield (8 steps). β-Lactam 20 was converted to PS-6 (6) analog 28 in 22% overall yield using an eight step sequence.

Original languageEnglish
Pages (from-to)309-319
Number of pages11
JournalJournal of Antibiotics
Volume40
Issue number3
Publication statusPublished - 1987 Jan 1
Externally publishedYes

Fingerprint

Lactams
Carbapenems
Imines
Esters
Hempa
Lithium
PS 5
PS-6

ASJC Scopus subject areas

  • Molecular Medicine
  • Pharmacology

Cite this

Ester-imine condensations : Preparation of racemic intermediates for the synthesis of the carbapenem antibiotics PS-5 and PS-6. / Ha, Deok-Chan; Hart, D. J.

In: Journal of Antibiotics, Vol. 40, No. 3, 01.01.1987, p. 309-319.

Research output: Contribution to journalArticle

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