Anthraquinones sugars

The use of certain vanadium compounds as catalysts has been increasing. Vanadium oxy trichloride is a catalyst in making ediylene-propylene rubber. Ammonium metavanadate and vanadium pentoxide aie used as oxidation catalysts, particularly in the production of polyamides, such as nylon, in the manufacture of H>S04 by the contact process, in the production of phdialic and maleic anhydrides, and in numerous other oxidation reactions, such as alcohol to acetaldehyde, anthracene to anthraquinone, sugar to oxalic acid, and diphenylamine to carbazole. Vanadium compounds have been used for many years 111 die ceramics field for enamels and glazes. Colors are produced by various combinations of vanadium oxide and silica, zirconia, zinc, lead, tin, selenium, and cadmium. Vanadium intermediate compounds also are used in the making of aniline Mack used by the dye industry... 

For the extraction of colourants from Rubia tinctorum (Figure 13.2) roots, mostly methanol, [42] water-methanol (with the addition of n-amyl alcohol in the case of lake extraction)[19,20] or water-ethanol solutions[38] are used. Additional hydrolysis can be performed with hydrochloric acid[8,19,20,34] and trifluoroacetic acid,[42] but also with madder root enzymes,[42] responsible for cleavage of anthraquinone glycosides into the corresponding aglycones and sugars. 

The molecular structure of the anticancer drug daunomycin is shown in Fig. 1. It consists of an anthraquinone ring system (aglycon), the portion which intercalates into the DNA [15], and an amino sugar group (daunosamine), which stays in the DNA minor groove. 

All anthracyclines possess one or more chelated OH groups and show therefore at least one signal in the offset region. As for anthraquinones [18], these peri-OH shifts are strongly dependent of the substituent pattern of the chromophore, however, are scarcely influenced by substituents in positions 8 and 9 (A3< 0.03). Hydroxy groups or sugar residues both in C-7o or C-10)8... 

The anthrone is the reduction product of anthraquinone and was recognized first as spiecific reagent for several carbohydrates by Dreywood (1946) because sugar solution in concentrate sulphuric add form the blue-greenish colour characteristic and since anthrone has been used widely as suitable and sp>ecific reagent for sugar colorimetric dosage. 

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