Total Synthesis of (-)-lasubine II by the conjugate addition and intramolecular acylation of an amino ester with an acetylenic sulfone.
[reaction: see text] The conjugate addition of methyl (S)-(2-piperidyl)acetate (3) to 2-(3,4-dimethoxyphenyl)-1-(p-toluenesulfonyl)ethyne (4), followed by LDA-promoted intramolecular acylation, stereoselective reduction, and desulfonylation, afforded (-)-lasubine II.
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Thomas G
TG
Department of Chemistry, University of Calgary, Alberta, Canada T2N 1N4. tgback@ucalgary.ca
Hamilton
Michael D
MD
D000114:Acetylene / Q000737:chemistry*; D000215:Acylation; D007202:Indicators and Reagents; D029561:Lythraceae / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D010946:Plants, Medicinal / Q000737:chemistry; D011807:Quinolizines / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism; D013450:Sulfones / Q000737:chemistry
D007202:Indicators and Reagents; D011807:Quinolizines; D013450:Sulfones; C414385:lasubin I; D000114:Acetylene