Amylose cyclohexaamylose

In contrast to the reaction of cyclohexaamylose with 1, no enantiomeric specificity is observed in the reaction of this material with cyclohepta-amylose (Paton and Kaiser, 1970). This loss of specificity upon increasing... 

The rotations of the Schardinger dextrins were calculated from data of ref. 43. According to currently accepted nomenclature tetraamylose is Schardinger s a-dextrin, or cyclohexaamylose diamylose is an alcohol-containing complex of a-dextrin hexa-amylose is Schardingers /J-dextrin, or cycloheptaamylose. 

Rees DA (1970) Conformational analysis of polysaccharides. Part V. The characterization of linkage conformations (chain conformations) by optical rotation at a single wavelength. Evidence for a distortion of cyclohexaamylose in aqueous solution. Optical rotation and the amylose conformation. J Chem Soc B 877-884... 

The parallel between the cyloamyloses and V-amyloses helped to explain the well-known blue colour of starch-iodine complexes a series of intensely coloured complexes of cyclohexaamylose, iodine and metal iodides had chains of iodine atoms in the central cavity of stacks of cyclohexaamyloses. The blue colour was thought to arise from charge transfer interactions amongst the I2 molecules and the linear and ions trapped in the central cavity. 

Figure 4.51 Relationship between cyclohexaamylose and a V-amylose with six residues per turn.

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