Transglycosylation synthesis

Hydrolysis and Transglycosylation Investigated in Micro Reactors Organic synthesis 27 [OS 27] Hydrolysis of p-nitrophenyl-y D-galactopyranoside... 

It should be emphasized that, although lipid-activated sugars provide the only well known mechanism for transglycosylation reactions occurring across a membrane, other mechanisms cannot be precluded. More, active research is needed in order to elucidate the mechanism of synthesis of several plant glycans. 

In summary, the general equation for the synthesis of complex saccharides through transglycosylation may be expressed as follows. 

All naturally occurring fungal strains of Trichoderma require an inducer for cellulase synthesis. In the absence of an inducer such as cellulose, cellobiose (21,22), or sophorose (12,13,14,23), Trichoderma does not make any detectable cellulase complex enzymes. The true physiological inducer of cellulase is currently unknown. Insoluble cellulose is presumably not such an inducer since there is no way for the internal cell machinery to sense the presence of this insoluble material. However, a small transglycosylation product such as sophorose, 2-0-/ -glucopyranosyl-D-glucose, may well be the natural inducer. 

T. Takamoto, R. Sudoh, and T. Nakagawa, Study on nitro sugars. Part II. Synthesis of benzyl 3,5-di-0-benzyl-2-deoxy-2-nitro-a-D-xylofuranoside and its transglycosylation with alkali, Carbohydr. Res., 27 (1973) 135-140. 

Uchida et al.220b reported the synthesis of 6m-deoxy maltodextrins by B. macerans CGTase transglycosylation reactions between mono-6-O-p-toluene sulfonyl cyclomal-tohexaose and maltose. The best inhibitors for human salivary a-amylase and human pancreatic a-amylase were 6m-deoxy maltotetraose and 6m-deoxy maltopentaose. 

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