title: Synthesis of glycosyl amino acids by light-induced coupling of photoreactive amino acids with glycosylamines and 1-C-aminomethyl glycosides.
abstract: The glycosylamines of O-acetyl-protected GlcNAc and chitobiose, as well as two partially unprotected 1-C-aminomethyl glucosides, were photochemically coupled with orthogonally protected N-aspartyl-5-bromo-7-nitroindoline derivatives. The reactions proceeded under neutral conditions by irradiation with near-UV light. The glycosyl asparagines with N- or C-glycosyl linkages were afforded in 60-85% yield on a 10-70 mg scale. Moreover, the ability of a highly photoreactive N-glutamyl-4-methoxy-7-nitroindoline derivative to acylate amino saccharides was tested. Upon irradiation in the presence of a dimeric 1-C-aminomethyl glycoside, or a glycosylamine, the corresponding glycosyl glutamines were obtained in 50% and 30% yield, respectively. Preparations of the photoreactive aspartates and the 1-C-aminomethyl glycosides are also described.
authors.affiliation: Department of Chemistry, University of the Pacific, Stockton, CA 95211, USA.
authors.forename: Ondrej
authors.initials: O
authors.lastname: Simo
authors.forename: Vincent P
authors.initials: VP
authors.lastname: Lee
authors.forename: Alexander S
authors.initials: AS
authors.lastname: Davis
authors.forename: Christian
authors.initials: C
authors.lastname: Kreutz
authors.forename: Paul H
authors.initials: PH
authors.lastname: Gross
authors.forename: Patrick R
authors.initials: PR
authors.lastname: Jones
authors.forename: Katja
authors.initials: K
authors.lastname: Michael
mesh_terms: D000215:Acylation; D000596:Amino Acids / Q000138:chemical synthesis* / Q000737:chemistry / Q000528:radiation effects*; D001216:Asparagine / Q000138:chemical synthesis; D001224:Aspartic Acid / Q000138:chemical synthesis; D002236:Carbohydrate Conformation; D004187:Disaccharides / Q000737:chemistry / Q000528:radiation effects; D005960:Glucosides / Q000138:chemical synthesis*; D006001:Glycoconjugates / Q000138:chemical synthesis / Q000737:chemistry; D006027:Glycosides / Q000737:chemistry*; D006031:Glycosylation; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D014466:Ultraviolet Rays
chemical_list: D000596:Amino Acids; D004187:Disaccharides; D005960:Glucosides; D006001:Glycoconjugates; D006027:Glycosides; D001224:Aspartic Acid; C032438:chitobiose; D001216:Asparagine