10148-66-0Relevant articles and documents
Asymmetric synthesis of α-amino-β-hydroxy acids using a chiral pyridoxal-like pyridinophane-zinc complex as an enzyme mimic; scope and limitation
Ando,Watanabe,Kuzuhara
, p. 88 - 90 (1990)
A chelate complex (4) with high homogeneity was precipitated upon stirring a mixture of zinc(II) ion and a Schiff base produced from glycine and (R)- or (S)-15-formyl-14-hydroxy-2,8-dithia[9](2,5)pyridinophane, chiral pyridoxal-like pyridinophane. A four-coordinated zinc chelate complex was newly proposed as the structure of 4. Aldol condensations between 4 and several aldehydes were attempted at pH 10.0. Only small linear chain aldehydes, such as acetaldehyde and propionaldehyde, could react with 4 under these conditions to give the corresponding α-amino-β-hydroxy acid in the range of 27-77% enantiomeric excess.
Modular solid-phase synthesis of teroxazoles as a class of α-helix mimetics
Pinto Gomes, Cristiano,Metz, Alexander,Bats, Jan W.,Gohlke, Holger,Goebel, Michael W.
supporting information; experimental part, p. 3270 - 3277 (2012/07/02)
α-Helices are ubiquitous structural elements of proteins and are important in molecular recognition. Small molecules mimicking α-helices have proven to be valuable biophysical probes or modulators of protein-protein interactions. Here, we present modeling studies and the modular solid-phase synthesis of teroxazole derivatives as a new class of α-helix mimetics. The synthesis is compatible with a variety of functional groups and should thus be generally applicable for generating diversely substituted oligo-oxazole scaffolds. The teroxazole scaffold is predicted to be polar and to project peptidomimetic side chains at positions i, i+3, and i+6 of an α-helix, which complements projection patterns of existing helix mimetics. The scaffold retains sufficient conformational flexibility to conform to induced-fit models of protein-protein interaction inhibition. Copyright
Stereoselective Synthesis of Threo and Erythro β-Hydroxy and β-Disubstituted-β-Hydroxy α-Amino Acids
Blaskovich, Mark A.,Evindar, Ghotas,Rose, Nicholas G. W.,Wilkinson, Scott,Luo, Yue,Lajoie, Gilles A.
, p. 3631 - 3646 (2007/10/03)
Optically pure N-protected serine aldehyde equivalents can be prepared by the protection of the carboxylic group of serine by a cyclic ortho ester. Alkylation of N-Cbz-, N-Fmoc- or N-Boc-protected serine with oxetane tosylate 1 or bromide 2 gives the corresponding oxetane esters 4a-c which can easily be converted to the cyclic ortho esters 5a-c. A variety of unusual threo β5-hydroxy amino acids have been synthesized by Grignard addition to these optically pure serine aldehyde equivalents. The erythro diastereomers can be obtained by oxidation of the initial threo adduct followed by reduction with LiBH4. Also described is a general approach for the diastereoselective synthesis of optically pure β,β-dialkyl-β-hydroxy α-amino acids. These highly substituted amino acids are prepared by a sequence of Grignard addition to the optically active serine aldehyde equivalent, followed by oxidation of the initial adduct, and a second Grignard addition to the resulting ketone. The hydroxy adduct is obtained with very high diastereoselectivity (84-96% de). All four diastereomers can be selectively synthesized by varying the order of the Grignard additions and the chirality of the initial synthon. Removal of the protecting groups can be effected in very mild conditions, giving excellent yields of highly substituted amino acids in high diastereomeric purity.
