ChemInform Abstract: Conformationally Constrained Dipeptides. Obtention of Enantiomerically Pure 6-Acetamido-5-oxo-1,2,3,5,6,7-hexahydro-3-indolizine Carboxylic Acid

1999

amino acids, peptides

amino acids, peptides U 0400 Conformationally Constrained Amino Acids: A Convenient Approach 29 - 193 to cis-2,3-Methano-GABAs. — Cyclopropyl amino acids are prepared starting from bromo amides (I). The latter are cyclized to diastereomeric lactams (II) followed by dehydrobromination affording bicyclic compounds (III). Following N-deprotection and HCl-mediated opening of the lactam ring provides the target acids (V). — (FORTI, LUCA; GHELFI, FRANCO; LEVIZZANI, STEFANO; PAGNONI, UGO M.; Tetrahedron Lett. 40 (1999) 16, 3233-3234; Dip. Chim., Univ. Modena, I-41100 Modena, Italy; EN)

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