Researchers of the Zelinsky Institute are studying a stereoselective method for the synthesis of aryl glycosides

Functionalized aryl glycosides are actively used to obtain neoglycoconjugates, which are in great demand in the rapidly developing areas of glycobiology and glycomedicine. One of the most commonly used methods for the stereoselective synthesis of various aryl glycosides is the glycosylation reaction under phase transfer catalysis using a glycosyl halide and a phenol derivative as the starting compounds.

Scientists of the Laboratory of Glycochemistry of the Zelinsky Institute have been conducting research on the synthesis and chemical properties of sialic acid derivatives over the past years. In one of their recent works, they studied the reaction of obtaining an aryl glycoside from N-acetylsialyl chloride and a substituted phenol in a flow reactor under phase transfer catalysis conditions. It was shown that in addition to the mixing mode and flow rate, the concentration of the glycosyl donor (N-acetylsialyl chloride) also affected the stereoselectivity of this reaction. Thus, by changing only the concentration of the initial compound, it is possible to switch the reaction from completely non-selective to almost stereospecific. This observation can be explained by the fact that the real reacting species in this process are supramolecular aggregates (supramers), and not individual molecules of the reacting substances. Carrying out the reaction in a flow reactor makes it easy to scale up the production of the target glycoside with a relatively high yield and high stereoselectivity.
 

Source:

Ilya V. Myachin and Leonid O. Kononov Phase-Transfer Catalyzed Microfluidic Glycosylation: A Small Change in Concentration Results in a Dramatic Increase in Stereoselectivity // Catalysts 2023, 13, 313. DOI: 10.3390/catal13020313.