Automated carbohydrate synthesis

Fig. 2. Schematic description of the automated carbohydrate synthesis machine. (See color insert.)...

The instrument chosen for the evaluation of carbohydrate synthesis was an ABI-433 peptide synthesizer (Fig. 2). The instrument was adapted for carbohydrate synthesis and customized coupling cycles were developed. A specially designed low-temperature reaction vessel was installed and interfaced with a commercially available cooling device.13 The necessary reagents were loaded onto the instrument ports and reaction conditions were programmed on the computer, in a fashion similar to the automated synthesis of peptides. 

An automated solid-phase method necessitates a polymer support and a linker that are compatible with the reagents used in carbohydrate synthesis. Several strategies have been developed that address functional group compatibility and swelling of the polymer support. Of these strategies, a family of olefinic linkers has proven to be readily cleaved under neutral... 

Scheme 3. Automated carbohydrate synthesis using glycosyl phosphates.

Automated carbohydrate synthesis allows for the production of complex carbohydrates orders of magnitude faster than other approaches. This advance has the potential to parallel the breakthroughs achieved by researchers in the peptide and DNA fields that opened up the pro-teomic and genomic eras in biotechnology. By increasing the scope of the carbohydrate building block library and streamlining the reaction conditions further we anticipate that automated solid-phase carbohydrate synthesis will become the method of choice for carbohydrate production. 

The advances in automation presented constitute an important first step toward alleviating the difficulty incumbent to carbohydrate synthesis. 

Many strategies have been and are still being developed to access oligosaccharides by chemical synthesis. This chapter focuses on recent developments in the automated solid-phase synthesis of oligosaccharides and emphasizes the recent advances of novel microreactor techniques for carbohydrate synthesis. 

P. H. Seeberger, Automated carbohydrate synthesis to drive chemical glycomics, Chem. Commun., (2003) 115-1121. 

Although of limited scope, one approach for solid phase carbohydrate synthesis has actually incorporated coupling chemistry into an automated solid phase oligosaccharidesynthe-sizer (123). In addition, there is the use of gly-cosyltransferase-regenerating beads that are potentially applicable to automated oligosaccharide synthesis (124). 

Plante OJ, Seeberger PH. Recent advances in automated solid-phase carbohydrate synthesis from screening to vaccines. Curr Opin Drug Dis Dev 2003 6 521-525. 

While efforts are ongoing to solve the challenge of automated solid-phase synthesis, parallel studies are underway to develop new techniques to speed solution-phase carbohydrate synthesis, particularly for situations when the aforementioned one-pot approach is not applicable. One exciting technique,... 

Keywords Automation Carbohydrate synthesis Oligosaccharides Solid-phase... 

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