The Rotatory Dispersion and Stereochemistry of Organic Compounds. IX. The Nitrates of Glucose

Abstract

Abstract We have measured the rotatory dispersion (RD) and the ultraviolet absorption of twelve nitrates of glucopyranosides carrying a nitrate chromophore, –O–NO2, in the position of the carbon atoms 1, 2, 3, 4, and 6. On the basis of the experimental results and of those results already reported concerning four nitrates, studies have been made as to the correlation between the configuration and the Cotton effect. The sign of the Cotton effect has been determined by the RD curve as well as by the dispersion constant as computed from the dispersion data. A regular relation has been found, namely, irrespective of the position of the nitrate group on the carbon atom, α-glucosides with α nitrate chromophore in the α- or (d)-configuration show negative Cotton effects, while the sign of the Cotton effects of the corresponding β-glucosides is positive. On the contrary, α-glucosides with a nitrate chromophore in the β- or (l)-configuration show positive Cotton effects, while the sign of the Cotton effects of the corresponding β-glucosides is negative.