170642-28-1Relevant articles and documents
Novel design of bicyclic β-turn dipeptides on solid-phase supports and synthesis of [3.3.0]-bicyclo[2,3]-leu-enkephalin analogues
Gu, Xuyuan,Ying, Jinfa,Agnes, Richard S.,Navratilova, Edita,Davis, Peg,Stahl, Gannon,Porreca, Frank,Yamamura, Henry I.,Hruby, Victor J.
, p. 3285 - 3288 (2007/10/03)
(Chemical Equation Presented) External bicyclic β-turn dipeptide mimetics provide an excellent design approach that can offer a rich chiral ensemble of structures with different backbone conformations. We report herein a novel design of a convergent combinatorial synthetic methodology, which is illustrated by the solid-phase synthesis of a series of [3.3.0]-bicyclo [2,3]-Leu-enkephalin analogues. The reactions were optimized and the epimeric configurations were determined by 2D NMR spectroscopy. Biological assays show that these analogues have more potent δ binding affinity and bioactivity for δ vs μ opioid receptor, which may be related to the different conformations preferred by these analogues in our modeling studies.
Synthesis of enantiopure functionalized pipecolic acids via amino acid derived N-acyliminium ions
Rutjes, Floris P. J. T.,Veerman, Johan J. N.,Meester, Wim J. N.,Hiemstra, Henk,Schoemaker, Hans E.
, p. 1127 - 1135 (2007/10/03)
The synthesis and enzymatic resolution of a novel vinylsilane-containing amino acid is described. Derivatization of this and other olefinic amino acids followed by subjection to standard N-acyliminium ion cyclization conditions provides the corresponding pipecolic acid derivatives with - in most cases - complete conservation of enantiopurity. In addition to studying the scope of this reaction, details of the N-acyliminium ion cyclization including an aza Cope equilibrium are highlighted.