112419-82-6Relevant academic research and scientific papers
Michael addition reactions between chiral Ni(II) complex of glycine and 3-(trans-enoyl)oxazolidin-2-ones. A case of electron donor - Acceptor attractive interaction-controlled face diastereoselectivity
Cai,Soloshonok,Hruby
, p. 1339 - 1350 (2001)
This study has demonstrated that the readily available and inexpensive 3-(trans-3′-alkyl/arylpropenoyl)oxazolidin-2-ones, featuring high electrophilicity and conformational homogeneity, are synthetically superior Michael acceptors over the conventionally used alkyl enoylates, allowing for a remarkable improvement in reactivity and, in most cases, diastereoselectivity of the addition reactions with a Ni(II) complex of the chiral Schiff base of glycine with (S)-o-[N-(N-benzylprolyl)-amino]benzophenone. Kinetically controlled diastereoselectivity in the corresponding Michael addition reactions between the Ni(II) complex of glycine and the oxazolidin-2-ones was systematically studied as a function of steric, electronic, and position effects of the substituents on the starting Michael acceptor. In both aliphatic and aromatic series the simple diastereoselectivity was found to be virtually complete, affording the products via the corresponding TSs with the approach geometry like. The face diastereoselectivity of the reactions between the Ni(II) complex of glycine and the 3-(trans-3′-alkylpropenoyl)oxazolidin-2-ones was found to depend exclusively on the steric bulk of the alkyl group on the starting Michael acceptor. In contrast, the face diastereoselectivity in the reactions of aromatic oxazolidin-2-ones with the Ni(II) complex of glycine was shown to be controlled predominantly by the electronic properties of the aryl ring. In particular, the additions of the Ni(II) complex of glycine with 3-(trans-3′-arylpropenoyl)oxazolidin-2-ones, bearing electron-withdrawing substituents on the phenyl ring, afforded the (2S,3R)-configured products with synthetically useful diastereoselectivity and in quantitative chemical yields, thus allowing for an efficient access to the sterically constrained β-aryl-substituted pyroglutamic and glutamic acids.
Chemoenzymatic synthesis of glutamic acid analogues: Substrate specificity and synthetic applications of branched chain aminotransferase from Escherichia coli
Xian, Mo,Alaux, Sebastien,Sagot, Emmanuelle,Gefflaut, Thierry
, p. 7560 - 7566 (2008/03/11)
(Chemical Equation Presented) A new route to α-keto acids is described, based on the ozonolysis of enol acetates obtained from α-substituted β-keto esters. Escherichia coli branched chain aminotransferase (BCAT) activity toward a variety of substituted 2-oxoglutaric acids was demonstrated analytically. BCAT was shown to have a broad substrate spectrum, complementary to that of aspartate aminotransferase, and to offer access to a variety of glutamic acid analogues. The usefulness of BCAT was demonstrated through the synthesis of several 3- and 4-substituted derivatives.
A stereoselective synthesis of 3-substituted (S)-pyroglutamic and glutamic acids via OBO ester derivatives
Herdeis, Claus,Kelm, Bernd
, p. 217 - 229 (2007/10/03)
(S)-Pyroglutamic acid is transformed to the Cbz-protected 4-methyl-2,6,7-trioxabicyclo[2.2.2] octane (OBO) ester. This ortho ester functionality is employed as a bulky steering group for stereoselective introduction of alkyl and aryl groups via 1,4-cuprate addition to 3,4-unsaturated pyroglutamates. After deprotection and ringopening, 3-substituted glutamic acids are obtained.
Synthesis of Enantio- and Diastereo-isomerically Pure β- and γ-Substituted Glutamic Acids via Glycine Condensation with Activated Olefins
Belokon, Yuri N.,Bulychev, Aleksandr G.,Ryzhov, Mikhail G.,Vitt, Sergei V.,Batsanov, Andrei S.,et al.
, p. 1865 - 1872 (2007/10/02)
The glycine fragment in the nickel(II) complex formed from the Schiff base of glycine and (S)-o-benzophenone undergoes base-catalysed Michael addition in methanol in the presence of MeONa to the activated olefins methyl acrylate, acrylonitrile, methyl methacrylate, acrolein, and methyl trans-cinnamate.Complexes of substituted (S)-glutamic acid or its derivatives were formed in good chemical yields with almost complete diastereoselection at the α-carbon atom of the amino acid moiety.Diastereoselection at the β- and γ-atoms was not significant, but the isomeric complexes could be easily separated chromatogrphically.Cleavage of the pure diastereoisomers with aqueous HCl gave, in good yields, optically pure glutamic acids and regenerated the original chiral reagent.The configurations of the amino acid β- and γ-carbon atoms were determined by 1H n. m. r. spectroscopy and crystal structure X-ray analysis of the corresponding original complexes.The addition to acrolein, catalysed by triethylamine in methanol, leads to the 1,4-adduct exclusively.The amino acid thus obtained could be converted into (S)-proline by reduction with NaBH4.
