From Polymer to Size‐Defined Oligomers: An Expeditious Route for the Preparation of Chondroitin Oligosaccharides

A microbial–enzymatic strategy for producing chondroitin sulfate glycosaminoglycans

“…Recently, many studies have been conducted to extract CS from Prionace glauca (Vazquez, Blanco, Fraguas, Pastrana, & Perez‐Martin, ), Chinese sturgeon cartilage (Zhao et al, ), fish bone (He et al, ), and skate cartilage (Lignot, Lahogue, & Bourseau, ). In addition, several chemical methods for synthesis of chondroitin (Kobayashi, Fujikawa, & Ohmae, ; Lopin & Jacquinet, ; Sears & Wong, ), CS and its oligosaccharides (Eller, Collot, Yin, Hahm, & Seeberger, ; Lubineau & Bonnaffé, ) have been established. Specifically, Fujikawa, Ohmae, and Kobayashi () developed an enzymatic method to produce chondroitin 4‐sulfate by enzymatic polymerization of chemically‐synthesized CSA disaccharides with hyaluronidase.…”

From Polymer to Size‐Defined Oligomers: A Step Economy Process for the Efficient and Stereocontrolled Construction of Chondroitin Oligosaccharides and Biotinylated Conjugates Thereof: Part 1

“…The necessity to lock the d-galactosamine unit in the pyranose conformation through a 4,6benzylidene acetal before acetylation, thus avoiding the extensive formation of furanose derivatives, is still being discussed. [9] Because crucial cou-pling reactions were planned to be performed using Schmidts trichloroacetimidate glycosylation procedure, [14] acetal 3 was transformed in a first route into the crystalline a-imidate 5 by a classical sequence. This easily available glycosyl donor was used systematically to introduce the last disaccharide unit at the nonreducing end in the synthesis of oligomers.…”

“…Keywords: biotinylated sugars · carbohydrates · chondroitin · glycosylation · oligosaccharides mer. [9] Herein we describe the development of this step economy process for the straightforward construction of nonsulfated chondroitin oligomers and their biotinylated conjugates as probes for the study of the biosynthesis of CS.…”

Chondroitin sulfate: extraction, purification, microbial and chemical synthesis

“…In 2009, they continued to develop a step economy process for the construction of size‐defined chondroitin oligosaccharides (from di‐ to octasaccharide) as reducing species with a fluorophore and their biotinylated conjugates as probes for the study of ChS biosynthesis . Based on a glycan elongation strategy similar to those described by Lopin and Jacquinet in 2006 and starting from acetylated or benzoylated species 28 or 39 , they synthesized a collection of oligomers 33 , 42 , 43 and 44 (from di‐ to ocatsaccharide) fitted with a fluorophore group (NAP), which were subsequently transferred into 45–48 in good yield (67% to 86%) after catalytic hydrogenation (Fig. ).…”