title: A practical synthesis of N α-Fmoc protected L-threo-β-hydroxyaspartic acid derivatives for coupling via α- or β-carboxylic group.
abstract: A simple and practical general synthetic protocol towards orthogonally protected tHyAsp derivatives fully compatible with Fmoc solid-phase peptide synthetic methodology is reported. Our approach includes enantioresolution of commercially available D: ,L: -tHyAsp racemic mixture by co-crystallization with L: -Lys, followed by ion exchange chromatography yielding enantiomerically pure L: -tHyAsp and D: -tHyAsp, and their selective orthogonal protection. In this way N                            (                               α                            )-Fmoc protected tHyAsp derivatives were prepared ready for couplings via either α- or β-carboxylic group onto the resins or the growing peptide chain. In addition, coupling of tHyAsp via β-carboxylic group onto amino resins allows preparation of peptides containing tHyAsn sequences, further increasing the synthetic utility of prepared tHyAsp derivatives.
authors.affiliation: Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, FL 33431, USA.
authors.forename: Nina
authors.initials: N
authors.lastname: Bionda
authors.forename: Maré
authors.initials: M
authors.lastname: Cudic
authors.forename: Lidija
authors.initials: L
authors.lastname: Barisic
authors.forename: Maciej
authors.initials: M
authors.lastname: Stawikowski
authors.forename: Roma
authors.initials: R
authors.lastname: Stawikowska
authors.forename: Diego
authors.initials: D
authors.lastname: Binetti
authors.forename: Predrag
authors.initials: P
authors.lastname: Cudic
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000138:chemical synthesis / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: C011274:3-hydroxyaspartic acid; D001224:Aspartic Acid