Enantioselective synthesis of tricyclic amino acid derivatives based on a rigid 4-azatricyclo[5.2.1.0^2,6]decane skeleton

• Matthias Breuning,
• Tobias Häuser,
• Christian Mehler,
• Christian Däschlein,
• Carsten Strohmann,
• Andreas Oechsner and
• Holger Braunschweig

Beilstein J. Org. Chem. 2009, 5, No. 81, doi:10.3762/bjoc.5.81

• β-turn-inducing building blocks in peptidomimetics and for chiral auxiliaries in asymmetric organocatalysis. Keywords: amino acid; enantioselective synthesis; norbornane; polycyclic compounds; pyrrolidine; Introduction Unnatural amino acids with a rigid bowl-shaped backbone have received

Synthesis of new C^α-tetrasubstituted α-amino acids

• Andreas A. Grauer and
• Burkhard König

Beilstein J. Org. Chem. 2009, 5, No. 5, doi:10.3762/bjoc.5.5

• aldehydes are prone to give aldol products under the reaction conditions used, we were able to obtain the target cyclic amino acids in low to moderate yields and in some cases with good diastereoselectivity. Keywords: amino acid synthesis; Cα-tetrasubstituted α-amino acids; unnatural amino acids

• ][14]. Therefore a variety of Cα-tetrasubstituted α-amino acids have been developed in recent years and reported in the literature [15][16][17][18][19]. Recently our group reported as a new class of such unnatural amino acids Cα-tetrasubstituted tetrahydrofuran amino acids (TAAs), which were prepared