Asymmetric synthesis of propargylamines as amino acid surrogates in peptidomimetics

• Matthias Wünsch,
• David Schröder,
• Tanja Fröhr,
• Lisa Teichmann,
• Sebastian Hedwig,
• Nils Janson,
• Clara Belu,
• Jasmin Simon,
• Shari Heidemeyer,
• Philipp Holtkamp,
• Jens Rudlof,
• Lennard Klemme,
• Alessa Hinzmann,
• Beate Neumann,
• Hans-Georg Stammler and
• Norbert Sewald

Beilstein J. Org. Chem. 2017, 13, 2428–2441, doi:10.3762/bjoc.13.240

• sulfinamide provides chiral N-sulfinylimines, which were reacted with (trimethylsilyl)ethynyllithium to afford diastereomerically pure N-sulfinyl propargylamines. Diverse functional groups present in the propargylic position resemble the side chain present at the Cα of amino acids. Whereas propargylamines

• -butyl sulfinamide led to the enantiomerically pure sulfinylimines 3a and 3b, which were reacted with a variety of organometallic compounds, including iPrMgBr, MeMgBr and BnMgBr. The reaction of the enantiomerically pure N-sulfinylimines 3a and 3b with aliphatic organometallic nucleophiles resulted in

• (dr 51:49). In order to prepare phenylalanine analogoues, N-sulfinylimines 3a and 3b were reacted with benzylmagnesium bromide. However, only traces of the desired addition products could be detected by LC–MS analysis of the crude products. Approach II starts with the condensation of an aldehyde with

Studies on the interaction of isocyanides with imines: reaction scope and mechanistic variations

• Ouldouz Ghashghaei,
• Consiglia Annamaria Manna,
• Esther Vicente-García,
• Marc Revés and
• Rodolfo Lavilla

Beilstein J. Org. Chem. 2014, 10, 12–17, doi:10.3762/bjoc.10.3

• (Table 1, entry 10), without traces of the corresponding α-aminoamide. Different types of activated substrates displaying C=N bonds (N-sulfinylimines, oximes and hydrazones) were studied, but none of them reacted productively with isocyanides under the described conditions. Finally, the reaction with

Asymmetric synthesis of γ-chloro-α,β-diamino- and β,γ-aziridino-α-aminoacylpyrrolidines and -piperidines via stereoselective Mannich-type additions of N-(diphenylmethylene)glycinamides across α-chloro-N-sulfinylimines

• Gert Callebaut,
• Sven Mangelinckx,
• Pieter Van der Veken,
• Karl W. Törnroos,
• Koen Augustyns and
• Norbert De Kimpe

Beilstein J. Org. Chem. 2012, 8, 2124–2131, doi:10.3762/bjoc.8.239

• ; Mannich-type addition; N-sulfinylimines; stereoselectivity; Introduction In recent years, non-proteinogenic diaminocarboxylic acids have gained a lot of attention among organic chemists and biochemists [1][2][3]. This is due to the fact that these diaminocarboxylic acids are present as key structural

• potency of analogous α,β-diaminocarboxylamides exists [15]. The synthesis of chiral α,β-diaminocarboxylic acid derivatives by asymmetric Mannich-type addition of enolates across activated imines, e.g., N-sulfinylimines [16][17][18][19][20], is one of the most common and versatile methods in organic

• ) occupies the less hindered pseudoequatorial position, and the corresponding Li-adduct 7 are stabilized by the interaction between the Li-cation, the diphenylmethyleneamino group, and the sulfinylimine nitrogen. The reversal of the enantiotopic face selectivity in the reaction of the N-sulfinylimines 3 with