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• 552-66-9 daidzin 
• 9005-25-8 starch 
• 316790-20-2 (1S,3R,4R,5S,6R)-4,5-bis((4-methoxybenzyl)oxy)-3-(((4-methoxybenzyl)oxy)methyl)-2,7-dioxabicyclo[4.1.0]heptane 

Relevant academic research and scientific papers

Boronic-Acid-Catalyzed Regioselective and 1,2- cis -Stereoselective Glycosylation of Unprotected Sugar Acceptors via SNi-Type Mechanism

Regio- and 1,2-cis-stereoselective chemical glycosylation of unprotected glycosyl acceptors has been in great demand for the efficient synthesis of natural glycosides. However, simultaneously regulating these selectivities has been a longstanding problem in synthetic organic chemistry. In nature, glycosyl transferases catalyze regioselective 1,2-cis-glycosylations via the SNi mechanism, yet no useful chemical glycosylations based on this mechanism have been developed. In this paper, we report a highly regio- and 1,2-cis-stereoselective SNi-type glycosylation of 1,2-anhydro donors and unprotected sugar acceptors using p-nitrophenylboronic acid (10e) as a catalyst in the presence of water under mild conditions. Highly controlled regio- and 1,2-cis-stereoselectivities were achieved via the combination of boron-mediated carbohydrate recognition and the SNi-type mechanism. Mechanistic studies using the KIEs and DFT calculations were consistent with a highly dissociative concerted SNi mechanism. This glycosylation method was applied successfully to the direct glycosylation of unprotected natural glycosides and the efficient synthesis of a complex oligosaccharide with minimal protecting groups.

Regioselective and 1,2-cis-α-Stereoselective Glycosylation Utilizing Glycosyl-Acceptor-Derived Boronic Ester Catalyst

Regioselective and 1,2-cis-α-stereoselective glycosylations using 1α,2α-anhydro glycosyl donors and diol glycosyl acceptors in the presence of a glycosyl-acceptor-derived boronic ester catalyst. The reactions proceed smoothly to give the corresponding 1,2-cis-α-glycosides with high stereo- and regioselectivities in high yields without any further additives under mild reaction conditions. In addition, the present glycosylation method was successfully applied to the synthesis of an isoflavone glycoside.

Synthesis of β-maltooligosaccharides of glycitein and daidzein and their anti-oxidant and anti-allergic activities

The production of β-maltooligosaccharides of glycitein and daidzein using Lactobacillus delbrueckii and cyclodextrin glucanotransferase (CGTase) as biocatalysts was investigated. The cells of L. delbrueckii glucosylated glycitein and daidzein to give their corresponding 4′- and 7-O-β-glucosides. The β-glucosides of glycitein and daidzein were converted into the corresponding β-maltooligosides by CGTase. The 7-O-β- glucosides of glycitein and daidzein and 7-O-β-maltoside of glycitein showed inhibitory effects on IgE antibody production. On the other hand, β-glucosides of glycitein and daidzein exerted 2,2-diphenyl-1- picrylhydrazyl (DPPH) free-radical scavenging activity and supeoxide-radical scavenging activity.

Glycosylation of daidzein by the Eucalyptus cell cultures

The sequential glycosylation of a soybean isoflavone, daidzein, with cultured suspension cells of Eucalyptus perriniana and cyclodextrin glucanotransferase was studied. Daidzein was converted into two glycosylation products, daidzein 7-O-β-d-glucopyranoside (39%) and daidzein 7-O-[6-O-(β-d-glucopyranosyl)]-β-d-glucopyranoside (β-gentiobioside, 6%), by cultured E. perriniana cells. Further glycosylation of daidzein 7-O-β-glucoside with cyclodextrin glucanotransferase gave daidzein 7-O-[4-O-(α-d-glucopyranosyl)]-β-d-glucopyranoside (β-maltoside, 26%), daidzein 7-O-β-maltotrioside (15%), and daidzein 7-O-β-maltotetraoside (7%).