140422-54-4Relevant articles and documents
Straightforward synthesis of fluorinated amino acids by Michael addition of ethyl bromodifluoroacetate to α,β-unsaturated α-amino acid derivatives
Kondratov, Ivan S.,Bugera, Maxym Ya.,Tolmachova, Nataliya A.,Daniliuc, Constantin G.,Haufe, Günter
, p. 100 - 108 (2018)
Copper-mediated Michael addition of ethyl bromodifluoroacetate to N-protected α,β-unsaturated α-amino acid esters was applied for straightforward synthesis of γ,γ-difluorinated analogues of glutamic acid (compound 1) and glutamine (compound 10). Moreover, a proline-based, sterically constrained analog of γ,γ-difluoroglutamic acid (compound 24) was prepared.
General Fmoc-Based Solid-Phase Synthesis of Complex Depsipeptides Circumventing Problematic Fmoc Removal
Lobo-Ruiz, Ariadna,Tulla-Puche, Judit
supporting information, p. 183 - 192 (2020/01/24)
Development of an Fmoc-based solid-phase depsipeptide methodology has been hampered by base-promoted fragmentation and diketoperazine formation upon Fmoc group elimination. Such a strategy would be a useful tool given the number of commercially available Fmoc-protected residues. Herein we report that the addition of small percentages of organic acids to the Fmoc-removal cocktail proves effective to circumvent these drawbacks and most importantly, allowed the development of an exclusively solid-phase stepwise methodology to prepare a highly complex depsipeptide with multiple and consecutive esters bonds. Alongside, the optimal protecting group scheme for residue incorporation, which is not as straightforward as it is for traditional peptide synthesis, was explored. The developed stepwise strategy proved effective for the synthesis of a highly complex cyclodepsipeptide, being comparable to the yields obtained when using traditional combined chemistry approaches.
METHODS OF SYNTHESIZING AZTREONAM DERIVATIVES
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Paragraph 408, (2020/11/03)
Disclosed herein are aztreonam derivatives, therapeutic methods of using the aztreonam derivatives, and methods of synthesizing aztreonam derivatives. The aztreonam derivatives can be administered orally to provide orally bioavailable aztreonam.
