1,4-Glycosidic linked disaccharides

In this paper we concentrated on Maillard products derived from 1,4-glycosidic linked disaccharides, such as maltose or lactose. Carbohydrates with a 1,4-glycosidic link are of considerable relevance for food chemistry. For example, starch is one of the main components of many food stuffs. Maltose is an important degradation product of starch and occurs as such particularly in malted food, whereas the milk sugar lactose is found in dairy products. 

Dialkylstannylene acetals derived from a number of carbohydrate diols reacted with diacyl chlorides in the presence of a tertiary amine to give symmetrical, non-glycosidically linked disaccharides, such as compound The tungsten... 

The first syntheses of the ether-bridged and glycosidically-linked disaccharides (87) and (88), which occur in the anthracycline class II antibiotics (e.g. cinerubin B), have been reported. See Scheme 10 for the route to the former the latter was made by analogous use of methyl 3-0-acetyl-6-bromo-2,6-dideoxy-a-D-rif)o-hexopyranoside followed by inversion at C-6 by way of the 6-deoxy-5-ene. ... 

C-Glycosidically linked disaccharides have now become of considerable importance and a review has covered the preparation of such compounds as well... 

Similarly, per-O-trimethylsilylated mono- and P-linked disaccharides (lactose and cellobiose, not melibiose) could be converted into the corresponding a-glycosyl iodides, which upon SN2 displacement with CbT using TBACN mainly afforded P-cyano derivatives in good overall yields [191]. The cyanoglycosides were transformed into aminomethyl glycosides via reduction under mild conditions (Scheme 2.52). 

Widmalm et al.354 reported the measurement of 3J(C, H) couplings through glycosidic linkages in p-linked disaccharides and also for vicinally disubstituted trisaccharides. Widmalm with other co-authors355 reported the measurement of trans-glycosidic 3J(C,H) couplings in the trisaccharide 2 -fucosyllactose. 

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