Maltose derivatives

When two sugars are linked together, a glycosidic bond is formed between them (Figure 4.19), which is illustrated by the Belgian disaccharide4, maltose, derived from... 

We first describe a synthesis of alpha cyclodextrin. The synthetic plan is shown in Scheme 1. An immediate precxirsor for 1 could be the perbenzylated precursor 5, which could be cleaved to give a linear glucohexaosyl fluoride 6. This key intermediate 6 is obtainable from the maltose derivatives 8 and 9 through the intermediacy of the glucohexaose derivative 7 ... 

K. Bock and H. Pedersen, The substrate specificity of the enzyme amyloglucosidase (AMG). Part II. 6-Substituted maltose derivatives, Acta Chem. Scand. B, 42 (1988) 75-85. 

Reaction of peracetylated l-thio-a-o-glucopyranose (10a) with peracetylated 6-deoxy-6-iodomaltose (18), 6 -deoxy-6 -iodomaltose (21a) and 6 -deoxy-6 -iodomalto-oligosaccharides (21 b,21 c) gave the corresponding S-a-glucosylthio-maltose derivatives (20,23a-c) in excellent yields (Scheme 7) [24,28,29aj. 

Maltose is another important disaccharide. It can be produced on a large scale from starch, but its potential as a raw material for chemical industry needs to be explored. In order to achieve this objective, an understanding of the fundamental chemistry of maltose is essential. The purpose of this article is, therefore, to collate information on the reactions of maltose, and to illustrate some of the physical methods that have contributed to the characterization of maltose derivatives. 

The potential importance of unsaturated sugars as synthetic and biological intermediates is widely recognized. It is therefore surprising that only two unsaturated maltose derivatives, hexa-O-ace-tylmaltal123,124 (51) and methyl 2,3,6-trideoxy-5-0-(2,3,4-tri-0-acetyl-... 

C Chemical-Shift" Assignments for Some Maltose Derivatives... 

A Suzuki coupling between the calixarene 1,3-diboronic acid and the 4-bromo-phenylether of tetraacetyl derivatives of corresponding glucosides, followed by deacetylation led to the derivatives 32e70 and 32f.71 The mono maltose derivative 32g was prepared in a similar way. 

As a natural extension to the utility of silicon tethered radical acceptors for the preparation of C-glycosides, Xin, et al.,27 applied this technology to the preparation of a C-maltose derivative. This example, centering around the preparation of a C-disaccharide, will be discussed in detail in Chapter 8. 

The re osdective sul tion of several mono- and di-saccharide derivatives via dibutylstannylene acetals has been investigated methyl 4,6-0-bem dene-a-D-gluco- and -galacto-pyranoside were sulfated at 0-2 in 84 and 79% yield, respectively, and />-methoxyben I 6-0-/-butyidimethyIsil34-P-D-gaIactopyranoside at 0-3 in 92% yield " phenyl l-thio-3-lactoside gave the 3 -sulftte in 76% yield, accompanied by 10% of the 3, 6 -disul te, and similar results were obtained with phenyl 2-acetamido-2-deoxy-l-thio-P-lactoside," " whereas the maltose derivative 51 reacted preferentially at 0-2. "... 

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