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Updated: Aug 8, 2026

Synthesis of Esters Via a Greener Steglich Esterification in Acetonitrile
Published on: October 30, 2018
Total synthesis of stephanotic acid methyl ester
David J Bentley1, Alexandra M Z Slawin, Christopher J Moody
1Department of Chemistry, University of Exeter, UK.
Abstract:
[structure: see text]The methyl ester of the naturally occurring macrocyclic pentapeptide stephanotic acid, containing an unusual beta-substituted alpha-amino acid with a tryptophan C-6 to leucine beta-carbon link, has been synthesized. The key steps include the formation of this amino acid through a thioxo-oxazolidine intermediate and a Horner-Wadsworth-Emmons reaction using a phosphonoglycine, derived by a dirhodium(II)-catalyzed N-H insertion reaction, to give a dehydroamino acid and subsequent rhodium(I)-catalyzed asymmetric hydrogenation to introduce the modified tryptophan residue.
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