Convergent Synthesis of a Bifunctional GPI as a Universal Platform to Access Diverse GPI and GPI-Anchored Protein Probes.

A bifunctional glycosylphosphatidylinositol (GPI) anchor containing an azide and a biotin to facilitate additional functionalization via click chemistry and avidin conjugation, respectively, was synthesized by a convergent strategy using an orthogonal protection tactic. It is a general platform to rapidly access diverse GPI and GPI-anchored protein (GPI-AP) probes. Spin-labeled GPI and GPI-AP derived from this platform were used in a related study to show that GPI governs the membrane orientation of GPI-AP, validating GPI as a unique protein anchor.