title: In-peptide synthesis of di-oxazolidinone and dehydroamino acid-oxazolidinone motifs as β-turn inducers.
abstract: Small and easy-to-do mimetics of β-turns are of great interest to interfere with protein-protein recognition events mediated by β-turn recognition motifs. We propose a straightforward procedure for constraining the conformation of tetrapeptides lacking a pre-formed scaffold. According to the stereochemistry array, N-Ts tetrapeptides including Thr or PhSer (phenylserine) at the positions 2 or 3 gave rise in a single step to the sequences Oxd(2)-Oxd(3) or ΔAbu(2)-Oxd(3) (Oxd, oxazolidin-2-one; ΔAbu, 2,3-dehydro-2-aminobutyric). These pseudo-Pro residues displayed highly constrained ϕ, ψ, and χ dihedral angles, and induced clear β-turns or inverse turns of type I or II, as determined by extensive spectroscopic and computational analyses.
authors.affiliation: Department of Chemistry G. Ciamician, University of Bologna, via Selmi 2, 40126, Bologna, Italy.
authors.forename: Rossella
authors.initials: R
authors.lastname: De Marco
authors.forename: Arianna
authors.initials: A
authors.lastname: Greco
authors.forename: Sebastiano
authors.initials: S
authors.lastname: Rupiani
authors.forename: Alessandra
authors.initials: A
authors.lastname: Tolomelli
authors.forename: Claudia
authors.initials: C
authors.lastname: Tomasini
authors.forename: Silvia
authors.initials: S
authors.lastname: Pieraccini
authors.forename: Luca
authors.initials: L
authors.lastname: Gentilucci
mesh_terms: D008958:Models, Molecular; D009842:Oligopeptides / Q000138:chemical synthesis*; D023303:Oxazolidinones / Q000138:chemical synthesis*; D017433:Protein Structure, Secondary; D013237:Stereoisomerism
chemical_list: D009842:Oligopeptides; D023303:Oxazolidinones