Abstract: | Various poly- and oligosaccharides having a well-defined structure have successfully been synthesized via enzymatic polymerization of glycosyl fluoride monomers. All of the reaction proceeded under perfect control of regio- and stereochemistry. The relative direction of the synthetic cellulose (parallel or antiparallel) could be controlled in vitro in the enzyme-promoted propagation system, and based on these findings, a new concept “allos-selectivity” has been proposed. |