219953-66-9Relevant academic research and scientific papers
Stereocontrolled approaches to (+)- and (-)-γ-trifluoromethyl-GABOB, a new hydroxymethylene (statine) dipeptide isostere
Bravo, Pierfrancesco,Corradi, Eleonora,Pesenti, Cristina,Vergani, Barbara,Viani, Fiorenza,Volonterio, Alessandro,Zanda, Matteo
, p. 3731 - 3735 (1998)
Two efficient approaches to both enantiomers of syn-γ-trifluoromethyl γ-amino β-hydroxy butyric acid (γ-Tfm-GABOB) (10), a new hydroxymethylene (statine) dipeptide isostere, are described. One exploits the recently disclosed 'non-oxidative' Pummerer reaction, by means of which α-lithium alkyl sulfoxides are used as chiral α-hydroxyalkyl anion equivalents in the synthesis of β-amino alcohols. Trifluoropyruvaldehyde-N,S-ketal (R)-11, a novel stereochemically stable synthetic equivalent of α-amino trifluoropropanal, is used in the second approach.
Unusual nonchelation controlled allylation of a N-monoprotected α-amino aldehyde: Stereoselective entry to nonracemic trifluoromethyl dipeptide isosteres
Volonterio,Bravo,Corradi,Fronza,Meille,Vergani,Zanda
, p. 245 - 252 (2007/10/03)
An efficient synthesis of the non-racemic (66-68% e.e.) homoallylic β-trifluoromethyl β-amino alcohol (2S,3R)-9, a key intermediate in the synthesis of trifluoromethylated dipeptide isosteres and oligopeptides, was developed starting from N-Cbz-trifluoropyruvaldehyde-N,S-ketal (R)-1a. The correct syn-stereochemistry was achieved by combining two moderately stereoselective steps: (1) addition of allylmagnesium chloride to (R)-1a, occurring with unusual nonchelation control; (2) reductive desulfenylation of the phenylacetate 6 with NaBH4/pyridine.
