Synthesis of Gold Glyconanoparticles: Possible Probes for the Exploration of Carbohydrate‐Mediated Self‐Recognition of Marine Sponge Cells

The first step in marine sponge cell recognition and adhesion operates via a calcium‐dependent proteoglycan− proteoglycan interaction. For the marine sponge Microciona prolifera, one of the carbohydrate epitopes involved in the proteoglycan self‐recognition is a sulfated disaccharide [GlcpNAc3S(β1−3)Fucp]. Earlier surface plasmon resonance studies have demonstrated that the proteoglycan self‐recognition can be mimicked with synthetic β‐D‐GlcpNAc‐(1→3)‐α‐L‐Fucp‐(1→O), when multivalently presented by conjugation with bovine serum albumin. Here, the straightforward synthesis of water‐soluble gold glyconanoparticles coated with the glycosides β‐D‐GlcpNAc3S‐(1→3)‐α‐L‐Fucp‐(1→O)(CH2)3S(CH2)6SH, β‐D‐GlcpNAc3S‐(1→3)‐β‐L‐Fucp‐(1→O)(CH2)3S(CH2)6SH, β‐D‐GlcpNAc3S‐(1→O)(CH2)3S(CH2)6SH, α‐L‐Fucp‐(1→O)(CH2)3S(CH2)6SH, β‐D‐Glcp‐NAc3S‐(1→3)‐α‐L‐Galp‐(1→O)(CH2)3S(CH2)6SH, β‐D‐Glcp‐NAc‐(1→3)‐α‐L‐Fucp‐(1→O)(CH2)3S(CH2)6SH, and β‐D‐Glcp3S‐(1→3)‐α‐L‐Fucp‐(1→O)(CH2)3S(CH2)6SH is presented. Such supramolecular structures are excellent probes for studying carbohydrate−carbohydrate interactions by transmission electron microscopy, thereby generating information on the molecular level about the role of different functionalities in the self‐recognition process. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)