Polymer-Supported Stereoselective Synthesis of Tetrahydro‑2H‑oxazolo[3,2‑a]pyrazin-5(3H)‑ones from N‑(2-Oxoethyl)-Derivatized Dipeptides via Eastbound Iminiums

AGUSTINA LA VENIA; BOHUMIL DOLENSKY; VIKTOR KRCHNAK

ACS Combinatorial Science

AMER CHEM SOCIETY

Año: 2013 vol. 15 p. 162 - 167

2156-8952

Polymer-supported N-(2-oxo-ethyl)-derivatized Ser/Thr/Cys-containing dipeptides were synthesized and subjected to acid-mediated tandem N-acyliminium ion cyclization− nucleophilic addition to yield tetrahydro-2H-oxazolo- [3,2-a]pyrazin-5(3H)-ones. The reaction conditions and building-block combinations for stereoselective synthesis of the newly formed asymmetric carbon were developed. The synthesis was fully compatible with solid-phase peptide  synthesis, and the products serve as conformationally constrained peptidomimetics. The traceless synthesis of bicycles is also reported as part of this work. Nota: La publicación fue Tapa de Revista.