Thomas Vettiger, D. Seebach
Feb 12, 1990
Citations
0
Influential Citations
15
Citations
Journal
European Journal of Organic Chemistry
Abstract
Nucleophilic Ring Opening of Aryl 1-Nitro-1-cyclopropanecarboxylate with Sterically Protected, but Electronically Effective Carbonyl and Nitro Group. A New Principle of Amino Acid Synthesis The readily available [2,6-di-(tert-butyl)-4-methoxyphenyl] 1-nitro-1-cyclopropanecarboxylate (4) is ring-opened by nucleophilic attack of the amino groups of (S)-α-amino acid esters (products 20–26). Reduction of the nitro group gives rise to derivatives 27–30 of 2,4-diaminobutanoic acid which are connected with a second amino acid through the nitrogen in position 4 (2-substituted 6-amino-3-azaheptanedioic acids). In two cases, these were converted into enantiomerically and diastereomerically pure Freidinger's γ-lactam dipeptides (31, 32), which have previously been shown to mimic a peptide β-turn.