Inositolphosphoglycan Mediators: An Effective Synthesis of the Conserved Linear GPI Anchor Structure*

An effective new preparative synthesis of the conserved linear pseudopentasaccharide structure of the GPI anchors and of the full GPI structure has been carried out that has permitted obtaining both molecules in sufficient quantities as to perform further structural and biologic studies. The synthesis involves a 3+2 block synthesis strategy in which a conveniently protected Man α(1→4) GlcN₃ α(1→6) myo‐Ins building block, previously used in the synthesis of inositolphosphoglycan (IPG) mediators, is glycosylated with a protected Man α(1→2) Man trichloroacetimidate.