Catalysis disaccharides containing

In order to minimize such possible side-reactions as anomerization of glycosides and acetolysis of acetal structures, alternative techniques of acetylation have been studied. Whereas basic catalysis leads to severe complications in certain nitro sugar derivatives (see Section IV,2a and c pp. 124, 129), boron trifluoride etherate has proved to be an excellent agent for satisfactory acetylation of glycosides, O-benzyl-idenated glycosides, and disaccharides that contain a deoxynitro function.148,149... 

Carbohydrates have often been applied as starting materials for the synthesis of crown ethers, as they already contain hydroxy functions which are easy to incorporate in the crown ether structures. Crown ethers derived from commercial disaccharide D-lactose (7) have been used for the catalysis of the Michael addition. Benzyl 2,3,2 -tri-0-benzyl-3, 4 -0-isopropylidene-6,6 -0-(3,6,9-trioxaundccane-1,1 l-diyl)-/ -lactoside (8) was prepared by careful use of protection and benzyla-tion techniques as outlined11 similar crown ethers, e.g., 9, were obtained by analogous techniques12 13. 

---