13200-85-6Relevant articles and documents
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Radke et al.
, p. 2801 (1954)
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Solvent dependency though not solvate formation in the derivative-derivative resolution of N-formylphenylalanine
Palovics, Emese,Bereczki, Laura,Marthi, Katalin,Pokol, Gyoergy,Faigl, Ferenc,Fogassy, Elemer
, p. 2531 - 2536 (2007)
The efficiency of the resolution of N-formylphenylalanine was remarkably improved using (S)-(+)-2-benzylaminobutanol resolving agent in acetone. The efficiency of the resolution strongly depended on the quality of the solvent. Nevertheless, solvate formation did not occur during the process. The nature of the solvent-dependence was studied. The solid-melt binary phase diagram of the diastereomeric salts formed during the resolution by (S)-(+)-2-benzylaminobutanol was measured and discussed. It was recognized that the (S)-(+)-benzylaminobutanol (S)-(+)-N-formylphenylalanine salt exists in two polymorphic modifications. The effect of structurally related chiral and achiral auxiliary reagents in the above resolution was also studied. Thus, (S)-(+)-2-benzylaminobutanol was applied together with an (R)-(+)-1-phenylethylamine auxiliary resolving agent and benzylamine was used as a half-equivalent achiral basic reagent in a Pope-Peachey type resolution of N-formylphenylalanine by (S)-(+)-2-benzylaminobutanol. The results are compared to those obtained by the structurally related (R)-(+)-1-phenylethylamine chiral auxiliary.
THE FORMYLATION OF AMINO ACIDS WITH ACETIC FORMIC ANHYDRIDE.
MURAMATSU,MURAKAMI,YONEDA,HAGITANI
, p. 244 - 246 (1965)
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MgI2-chemoselective cleavage for removal of amino acid protecting groups: A fresh vision for peptide synthesis
Berthet, Mathéo,Martinez, Jean,Parrot, Isabelle
, (2017/03/30)
In the field of peptide synthesis, the key to a successful access to synthetic targets lies on a pertinent combination of protecting groups. Their choice is directed by their selective removal conditions. We present here the behavior of some of the most used protecting groups in peptide chemistry under experimental cleavage conditions, combining MgI2 with MW irradiation, using 2-Me-THF as a green solvent. In these experimental conditions, the benzyloxycarbonyl protecting group as well as the Merrifield resin can be re-considered in peptide chemistry.
Enantioselective Synthesis of Quaternary Δ4- and Δ5-Dehydroprolines Based on a Two-Step Formal [3+2] Cycloaddition of α-Aryl and α-Alkyl Isocyano(thio)acetates with Vinyl Ketones
Odriozola, Amaiur,Oiarbide, Mikel,Palomo, Claudio
supporting information, p. 12758 - 12762 (2017/09/25)
A divergent synthesis of optically active quaternary Δ4- and Δ5-dehydro prolines is developed based on the first catalytic enantioselective conjugate addition of α-substituted isocyano(thio)acetates to vinyl ketones that is general for both α-aryl and α-alkyl isocyano(thio)acetates. The new tetrasubstituted C?N stereocenter is formed without the need of any metal salt due to a bifunctional tertiary amine/squaramide catalyst, featuring a bulky polyaryl sidearm and an unusually short squaramide diamide H???H interatomic distance in the solid state.