Boric acid carbohydrates

Boeseken, J., The Use of Boric Acid for the Determination of the Configuration of Carbohydrates, IV, 189-210 Bonner, William A., Friedel-Crafts and Grignard Processes in the Carbohydrate Series, VI, 251-289 Bourne, E. J., and Peat, Stanley, The Methyl Ethers of D-Glucose, V, 145-190 Bourne, E. J. See also, Barker, S. A. 

Infrared and Raman spectroscopy are in current use fo r elucidating the molecular structures of nucleic acids. The application of infrared spectroscopy to studies of the structure of nucleic acids has been reviewed,135 as well as of Raman spectroscopy.136 It was noted that the assignments are generally based on isotopic substitution, or on comparison of the spectrum of simple molecules that are considered to form a part of the polynucleotide chain to that of the nucleic acid. The vibrational spectra are generally believed to be a good complementary technique in the study of chemical reactions, as in the study76 of carbohydrate complexation with boric acid. In this study, the i.r. data demonstrated that only ribose forms a solid complex with undissociated H3B03, and that the complexes are polymeric. 

Buffers of boric acid are useful in the pH range 8.5 to 10. Borate has the major disadvantage of complex formation with many metabolites, especially carbohydrates. 

A further aid in assigning vicinal cis hydroxy groups in carbohydrate residues of nucleosides and nucleotides makes use of boric acid as a complex shift reagent at various pH values [686]. In the presence of boric acid and at pH > 7 all complexing... 

The reactions of boric acid solutions with diols have been used for almost a century to examine structural differences among carbohydrates. The complexity of these reactions seems to arise not only from simple structural differences but also from differences in carbohydrate configuration and conformation. The precise nature of these reactions is not clear. Recent studies of the chemistry of polyol-boric acid solutions have clarified some aspects of these reactions that have important bearing on the structure of carbohydrates in solution. Nevertheless, some of the most fundamental questions about the nature of the reaction are still unanswered. 

If it is true that the structural form of D-glucose which reacts with boric acid is the a-D-pyranose form, then that form probably exists in a boat or twist conformation in the complex. This implies that the study of the stability constants of sugar borate ester might give information about the ability of various carbohydrates to form such boat or twist conformations (10, 21). 

Borax or borax-boric acid coatings containing a carbohydrate binder, with selected pigments. The borax or borax-boric acid combination will liberate the usual moisture when heated, with the binder and pigment furnishing some insulation. This type of coating has fair flame resistance. 

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