Carbohydrates Cotton effects

Optical rotatory dispersion studies on lactones of aldonic acids and other carbohydrate acids were made by Hirst et al.11 and later by Okuda et al.7S The latter workers related the absolute configuration at C-2 of aldono-1,4-lactones to the sign of the Cotton effect. 

Earlier structural studies of carbohydrates by CD involved introduction of suitable chromophores into the sugar molecule thereby affording derivatives which exibit Cotton effects. These include, among others, xanthates (4-8) or azides (9). Later it was found that some metal ions (10), i.e. copper (11,13), vanadate (14), chromium (15), molybdate (16-22), nickel (23) or cobalt (24,25) ions form complexes with carbohydrates, which show appreciable Cotton effects. 

A study of the circular dichroism of the ( , xr ) band of cyclic thiono-carbonates, derived from vicinal diols of carbohydrates, steroids, and generally rigid ring-systems, has shown that there is a relationship between the magnitude and sign of the Cotton effect of the (w, tt ) transition and the chirality of the five-membered thionocarbonate ring. ... 

The effect of color production from carbohydrate transformation in an alkaline pulping process, such as kraft pulping, is illustrated in Table III. Cotton linters, which originally had a brightness of 90.5%, were treated for 4 h at 180° with kraft liquor, with and without additives. Brightness was measured on paper made from the resulting, washed pulp. 

Kawabata A and Taylor JA, The effect of reactive dyes upon the uptake and antibacterial efficacy of poly(hexamethylene biguanide) on cotton . Carbohydrate Polymers, 67 (3), 2007, pp 375-389. 

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