title: Chirospecific synthesis of spirocyclic beta-lactams and their characterization as potent type II beta-turn inducing peptide mimetics.
abstract: [reaction: see text] Starting from natural proline, a practical chirospecific synthesis of spirocyclic beta-lactams of type 2 is described when a methylene moiety showing minimal steric demand is employed as a constraint element for adjusting the dihedral angle psi(i + 1). Employing the concept of self-reproduction of chirality, C-formylation of the oxazolidinone 5 afforded the key intermediate 7 taking advantage of an intermediate protection of the bridging element as a vinyl moiety. NMR- and IR-based conformational studies clearly indicated that spiro-beta-lactams of type 2 can serve as efficient beta-turn nucleators.
authors.affiliation: Department of Medicinal Chemistry, Emil Fischer Center, Friedrich Alexander University, Schuhstrasse 19, D-91052 Erlangen, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Bittermann
authors.forename: Peter
authors.initials: P
authors.lastname: Gmeiner
mesh_terms: D040761:Biomimetic Materials / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010455:Peptides / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D047090:beta-Lactams / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D010455:Peptides; D047090:beta-Lactams