162780-08-7Relevant academic research and scientific papers
A β-lactam-based stereoselective access to β,γ-dihydroxy α-amino acid-derived peptides with either α,β-like or unlike configurations
Palomo,Oiarbide,Landa,Esnal,Linden
, p. 4180 - 4186 (2007/10/03)
A concise access to α,β-dihydroxy α-amino acid-derived N-carboxy anhydrides (NCAs) with either like or unlike relative configuration is described. The key steps of the synthetic route are the preparation of the nonracemic 4-alkenyl β-lactams, through either Homer-type olefination of a common 4-formyl β-lactam or the Corey-Winter alkene synthesis applied to 4-dihydroxyalkyl β-lactams, followed by the Sharpless AD reaction, and a subsequent ring expansion of the corresponding 4-substituted 3-hydroxy β-lactams promoted by TEMPO. The opening of thus-prepared NCAs upon treatment with different O- and N-nucleophiles, including α-amino esters which lead to peptides, has also been studied under various reaction conditions.
A β-Lactam Framework as a β-Alanyl Dication Equivalent: New Synthesis of α-Amino Acid N-carboxy Anhydrides (NCAs) Derived from β-Substituted Alanines
Palomo, Claudio,Aizpurua, Jesus M.,Ganboa, Inaki,Maneiro, Elena,Odriozola, Beatriz
, p. 1505 - 1508 (2007/10/02)
Optically pure 4-formyl-3-hydroxy β-lactams are transformed into 4-methylaryl and 4-(2-ethylaryl) derivatives and converted into β-substituted alanine-derived NCAs through oxidation and Baeyer-Villiger rearrangement of the resulting α-keto β-lactams.
