A One-Pot Method For Removal Of Thioacetyl Group Via Desulfurization Under Ultraviolet Light To Synthesize Deoxyglycosides

Deoxyglycosides is an important carbohydrate compund,which is often found in modern pharmaceuticals.Deoxyglycosides has attracted extensive attention due to its great application potential in the field of pharmaceutical.However,there still exist some problems in the mainstream methods of synthesizing deoxyglycosides.So,it is necessary to find a green and efficient method to synthesize deoxyglycosides.The main research content of this article is to explore a new way of synthesizing deoxyglycosides,the main research results are shown as follow:1.Based on photochemical desulfurization reation of our group,we improved this method to get a green and efficient way of synthesizing deoxyglycosides.We use glycosides that contain thioacetyl as material,DMF as solvent,hydrazine hydrate as selective deacylation reagent,and the solution was stirred for 2-5 minutes under the room temperature.TLC method was used to detect if the reaction material was over,if the thioacetyl was completely converted into thiol,then 2.5 equivalent TCEP.HCl and molecular sieve were added into the reaction.Finally,the thiol group was removed by Ultraviolet Light for 1-2 hours to obtain deoxyglycosides.In order to test the usefulness of our method,we synthesized a series of glycosides that contain thioacetyl,then obtained corresponding deoxyglycosides by this method.The reaction yield of this method is between 70-90%.2.A pair of corresponding isomers(α configuration and β configuration)with relatively small polarity differences are often obtained in the glycosylation reaction,and this problem will not only reduce the yield of the products,but also makes separation difficult.The thioacetyl group have strong neighbor participation effects.If we introduce the thioacetyl group at position 2 of the donor glycoside,after the gycosylation reaction,the single configuration products would be obtained because of the neighbor participation effect of the thioacetyl group.Several single configuration glycosylation products were synthesized by this method.Then the thioacetyl group was removed by the above method to obtain corresponding 2-deoxyglycosides in a single configuration.