114645-17-9Relevant academic research and scientific papers
Complexation of chiral di (N-Protected α-Amino)-β-diketones with some transition metals
Saraireh, Ibrahim A.M.
, p. 4747 - 4752 (2013)
Chiral Di (N-protected a-amino)-b-diketones and its transition metal complexes have been synthesized. Di(N-protected a-amino)-b- diketones were prepared by reaction of activation of N-protected- a-amino acids (imidazolide) with a-diazoketones derived from natural amino acids in presence of lithium diisopropyl amid in tetrahydrofuran as a solvent at -78 °C and treatment the product with rhodium acetate to remove diazo group. The synthesized compounds were characterized by analytical techniques viz: IR, NMR and elemental analysis. The thermal stability of the newly synthesized metal complexes have been studied.
Synthesis and characterization of chiral di(N-protected-α-amino) diazo-β-diketones from α-diazoketones and imidazolides derived from amino acids
Saraireh, Ibrahim A.M.
supporting information; experimental part, p. 2023 - 2025 (2012/07/17)
Di(N-protected-α-amino)diazo-β-diketones were prepared by the reaction of activated N-protected-α-amino acids (imidazolides) with α-diazoketones, derived from natural amino acids, in the presence of lithium diisopropylamide in tetrahydrofuran as the solvent at -78 °C.
Synthesis of Fmoc-/Boc-/Z-β-amino acids via Arndt-Eistert homologation of Fmoc-/Boc-/Z-α-amino acids employing BOP and PyBOP
Vasanthakumar,Babu, V. V. Suresh
, p. 1691 - 1695 (2007/10/03)
A simple and efficient protocol for Arndt-Eistert chain homologation of Fmoc-/Boc-/Z-α-amino acids using BOP or PyBOP as a coupling agent to the corresponding β-amino acids, synthesizing the key intermediate α-diazoketones as crystalline solids in good yield is described.
Total synthesis of polyoximic acid
Hanessian, Stephen,Fu, Jian-Min
, p. 1812 - 1826 (2007/10/03)
The structure and stereochemistry of polyoximic acid, a degradation product of polyoxins, was originally designated as trans-3-ethylidene-L-azetidine-2-carboxylic acid. However, total synthesis revealed that the correct structure was in fact cis-3-ethylidene-L-azetidine-2-carboxylic acid, which was confirmed by X-ray crystallography. The synthesis of the trans-isomer was also done and its identity was confirmed by X-ray analysis as well. The key step for constructing the four-membered ring was a rhodium catalyzed carbenoid insertion into the N - H bond of a β-amino acid derivative. The stereoselectivity of the exo-double bond was controlled by conducting a Horner-Emmons-Wadsworth or a Wittig reaction to generate the trans- and cis-isomers, respectively. Weinreb's amide was used as a latent methyl group for the separation of trans and cis mixtures. The double bond stereochemistry of polyoximic acid in the parent polyoxin was also confirmed to be cis by extensive 2D NMR studies.
SYNTHESIS OF DIAZOKETONES DERIVED FROM α-AMINO ACIDS; PROBLEM OF SIDE REACTIONS
Plucinska, Krystyna,Liberek, Bogdan
, p. 3509 - 3518 (2007/10/02)
Optimum conditions of synthesis of eight diazoketones derived from optically active N-(t-butyloxycarbonyl)- and N-benzyloxycarbonylamino acids have been described.The problem of formation of by-products during Arndt-Eistert synthesis of β-homoamino acids at the stage of reaction of mixed anhydride with a weak nucleophile-diazomethane - has been discussed.
