Reacción #1890985

ord-bb3f7f1627ae4ee3a71c7899ba4cfbeb

Condiciones de reacción

Condiciones detalladas
See reaction.notes.procedure_details.

Procedimiento

To prepare trisaccharide oxazoline 3, the 4′,6′-O-benzylidene group in 15 was selectively removed by treatment with 80% aqueous AcOH at 50 C. The resulting compound 21 was then selectively glycosylated at the 6′-OH position with 2,3,4,6-tetra-O-benzoyl-β-D-mannopyranosyl trichloroacetimidate under the catalysis of TMSOTf to give trisaccharide derivative 23 (76%). De-O-benzoylation of 23 with subsequent O-acetylation afforded the O-acetylated pentenyl glycoside 25. Finally, compound 25 was converted to the oxazoline derivative by treatment with NIS/TESOTf to give 26, which was de-O-acetylated to provide trisaccharide oxazoline 3. On the other hand, the known chitobiose oxazoline 6[15] and the LacNAc-oxazoline 7[16] were prepared from O-acetylated N,N′-diacetylchitobiose and N-acetyllactosamine, respectively, following the reported procedure.[15, 16]

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US08354247B2uspto-grants-2013_01