Chemical synthesis of -arabinofuranosyl containing oligosaccharides derived from plant cell wall extensinsElectronic supplementary information (ESI) available: 1H NMR spectra of synthetic compounds. See DOI: 10.1039/c3ob40958a

Extensins are plant-derived glycoproteins that are densely modified by oligo-arabinofuranosides linked to hydroxyproline residues. These glycoproteins have been implicated in many aspects of plant growth and development. Here, we describe the chemical synthesis of a tetrameric (12)-linked arabinofuranoside that is capped by an (13)-arabinofuranoside and a similar trisaccharide lacking the capping moiety. The challenging (12)-linked arabinofuranosides were installed by using an arabinofuranosyl donor protected with 3,5- O -(di- tert -butylsilane) and a C-2 2-methylnaphthyl (Nap) ether. It was found that the cyclic silane-protecting group of the glycosyl donor greatly increased -anomeric selectivity. It was, however, imperative to remove the silane-protecting group of an arabinosyl acceptor to achieve optimal anomeric selectivities. The anomeric linker of the synthetic compounds was modified by a biotin moiety for immobilization of the compounds to microtiter plates coated with streptavidine. The resulting microtiter plates were employed to screen for binding against a panel of antibodies elicited against plant cell wall polysaccharides. Chemical synthesis of arabinofuranosides of plant glycoproteins that have been implicated in plant growth and development.