Regioselective syntheses of beta-N-linked glycoaminoacids and glycopeptides.
Acylation of tetra-O-pivaloyl-beta-D-galactopyranosylamine 2 by readily available N- (Cbz or Fmoc-alpha-aminoacyl) benzotriazoles under microwave irradiation proceeded diastereoselectively to give beta-N-glycoaminoacids 3a-d, (3c+3c') (compound numbers written within brackets represent a racemate or a diastereomeric mixture; compound numbers without brackets represent a single enantiomer) (83-92%), and glycosylated asparagine building block 9 (65%). N-Cbz-Protected peptidoylbenzotriazoles 4a-c similarly afforded beta-N-glycodipeptides 5a-c (76-81%). Regiospecific beta-N-linkage formation was established by 1D and 2D NMR techniques for 3b.
Katritzky
Alan R
AR
Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, USA. katritzky@chem.ufl.edu
Narindoshvili
Tamari
T
Draghici
Bogdan
B
Angrish
Parul
P
D000596:Amino Acids / Q000138:chemical synthesis* / Q000737:chemistry / Q000528:radiation effects; D006020:Glycopeptides / Q000138:chemical synthesis* / Q000737:chemistry / Q000528:radiation effects; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008872:Microwaves; D015394:Molecular Structure; D013237:Stereoisomerism
D000596:Amino Acids; D006020:Glycopeptides