title: Polymer-supported stereoselective synthesis of tetrahydro-2H-oxazolo[3,2-a]pyrazin-5(3H)-ones from N-(2-oxo-ethyl)-derivatized dipeptides via eastbound iminiums.
abstract: Polymer-supported N-(2-oxo-ethyl)-derivatized Ser/Thr/Cys-containing dipeptides were synthesized and subjected to acid-mediated tandem N-acylium 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.
authors: Department of Organic Chemistry, Faculty of Science, Palacký University, 17. Listopadu 12, 771 46 Olomouc, Czech Republic.
authors: Agustina
authors: A
authors: La Venia
authors: Bohumil
authors: B
authors: Dolenský
authors: Viktor
authors: V
authors: Krchňák
mesh_terms: D000080:Acetals / Q000737:chemistry*; D020650:Combinatorial Chemistry Techniques; D003500:Cyclization; D004151:Dipeptides / Q000138:chemical synthesis / Q000737:chemistry*; D015394:Molecular Structure; D010080:Oxazoles / Q000138:chemical synthesis* / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D047069:Pyrazolones / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000080:Acetals; D004151:Dipeptides; D010080:Oxazoles; D011108:Polymers; D047069:Pyrazolones