Variants of the azlactone synthesis in which analogues of azlactones are used are sometimes advantageous. Hydantoin (in Bergmann modification), thiohydantoin and rhodanine have each been employed as the enolate-forming component of the condensation.
[5][6]2,5-Diketopiperazine can be used as a methylene component as well; its condensation products with aromatic aldehydes, on reduction and hydrolysis give the corresponding amino acids.
[7][8][9]
Scope
In one study the Erlenmeyer amino acid synthesis was used in the heart of an L-m-tyrosine synthesis [10][11]
^H.D. Dakin. Aromatic aldehyde derivatives of proteins, peptides and amino acids. J. Biol. Chem. 1929, 84:675-682
^Alan D. Borthwick. 2,5-Diketopiperazines: Synthesis, Reactions, Medicinal Chemistry, and Bioactive Natural Products. DrugMolDesign, 15 Temple Grove, London NW11 7UA, U.K. Chem. Rev., 2012, 112 (7), pp 3641–3716. DOI: 10.1021/cr200398y
^A. M. Asiri. New Conjugated Systems Derived from Piperazine-2,5-dione. Molecules 2000, 5, 629-636
^Cara E. Humphrey, Markus Furegati, Kurt Laumen, Luigi La Vecchia, Thomas Leutert, J. Constanze D. Müller-Hartwieg, and Markus Vögtle (2007). "Optimized Synthesis of L-m-Tyrosine Suitable for Chemical Scale-Up". Organic Process Research & Development. 11 (6): 1069–1075. doi:10.1021/op700093y.((cite journal)): CS1 maint: multiple names: authors list (link)
^The benzyl ether of 3-hydroxybenzaldehyde1 reacts with the N-acetyl amide of glycine2, acetic anhydride and sodium acetate to the azlactone (not displayed) which is ring-opened with sodium acetate in methanol to dehydroamino acid 3. Hydrogenation gives the N-acyl-m-tyrosine methyl ester 4 (the benzyl ether group is also cleaved). This compound is racemic and kinetic resolution is brought about by an enzyme which is able to only cleave the methyl ester of the S-enantiomer (forming (S)-5 soluble in dichloromethane) leaving water-soluble (R)-4 untouched. The final step is amide cleavage to (S)-L-m-tyrosine 6
This browser is not supported by Wikiwand :( Wikiwand requires a browser with modern capabilities in order to provide you with the best reading experience. Please download and use one of the following browsers:
Your input will affect cover photo selection, along with input from other users.
X
Get ready for Wikiwand 2.0 🎉! the new version arrives on September 1st! Don't want to wait?
Oh no, there's been an error
Please help us solve this error by emailing us at support@wikiwand.com
Let us know what you've done that caused this error, what browser you're using, and whether you have any special extensions/add-ons installed.
Thank you!