Synthesis of the essential core of the human glycosylphosphatidylinositol (GPI) anchor
作者:Barbara Richichi、Lucio Luzzatto、Rosario Notaro、Giancarlo la Marca、Cristina Nativi
DOI:10.1016/j.bioorg.2010.12.002
日期:2011.4
role of GPIanchors is of paramount importance; however, we are still far from fully understanding the structure–function relationship of these molecules. One major limiting factor has been the tiny quantities available from natural sources; obtaining homogeneous and well-defined GPI structures by synthesis, is both a challenge and an attractive goal. We report here the convergent synthesis of the essential
Azido-Phenylselenylation of 3-<i>O</i>-Benzyl-2-Deoxy-5,6-<i>O</i>-Isopropylidene-D-<i>Arabino</i>-1,4-Anhydro-Hex-1-Enitol: Convenient Preparation of 2-Azido-2-Deoxy-D-Glucofurano-and Glucopyranoside Donors.
Azido-phenylselenylation of 3-O-benzyl-2-deoxy-5,6-O-isopropylidene-D-arabino-1, 4-anhydrohex-1-enitol (1) afforded an alpha/beta mixture of phenyl 2-azido-3-O-benzyl-2-deoxy-5,6-O-isopropylidene-1-seleno-D-glucofuranoside (2) together with a small amount of 3-O-benzyl-2-deoxy-5,6-O-isopropylidene-2-phenylseleno-D-glucofur?anosyl azide (3). Acetolysis of the mixture afforded 2-azido-2-deoxy-glucofuranosyl donor (4). Hydrolysis of the acetal group and of the selenoglycoside 2 followed by acetylation and removal of the anomeric acetate provide an efficient access to 5,6-di-O-acetyl-2-azido-3-O-benzyl-2-deoxy-D-glucopyranose (8), synthetic equivalent of D-glucosamine.