561303-35-3Relevant academic research and scientific papers
Synthesis of 2,6-bridged piperazine-3-ones by N-acyliminium ion chemistry
Veerman, Johan J. N.,Bon, Robin S.,Hue, Bui T. B.,Girones, Daniel,Rutjes, Floris P. J. T.,Van Maarseveen, Jan H.,Hiemstra, Henk
, p. 4486 - 4494 (2007/10/03)
Several 2-substituted and 2,5-disubstituted piperazine-3,6-diones were synthesized starting from readily available α-amino acids. After activation of a lactam carbonyl via introduction of a methoxycarbonyl group onto nitrogen, this carbonyl was selectively reduced. Treatment of the resulting urethane with protic acid generated the corresponding N-acyliminium ion, which was trapped by a nucleophilic C2-side chain to provide 2,6-bridged piperazine-3-ones. Several aromatic, heteroaromatic, and nonaromatic side chains were used as π-nucleophiles. In addition, the effect of the presence of a C5-methyl group on the stereochemical outcome of the cyclization was examined.
