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Sucrose anomeric configuration

Since the optical rotations of the D-fructopyranoses differ from those of the D-fructofuranoses in magnitude only (and never in sign), the anomeric configurations of the D-fructofuranoses are established. The /3 configuration derived in this way for the D-fructose moiety in sucrose coincides with the results of previous investigators. ... [Pg.93]

Fig. 2.9 Synthesis of sucrose. See text (Modified from Fig. 20-13 in Berg JM, Tymoczko JL and Stiver L. Biochemistry, 5th Ed. 2002. W.H. Freeman Co., New York to also show the phosphatase step). Note The diagram of fructose in this figure (red) is rotated so that its anomeric carbon atom (C2) lies to the right of the ring structure instead of the left as in a conventional diagram. Because of the rotation, it is not obvious that the fructose bond in sucrose is in the (3-anomeric configuration. Only the glucose bond is in the a-anomeric configuration. The conventional diagrams of glucose and fructose alone and in sucrose are illustrated in Fig. 15.6. Fig. 2.9 Synthesis of sucrose. See text (Modified from Fig. 20-13 in Berg JM, Tymoczko JL and Stiver L. Biochemistry, 5th Ed. 2002. W.H. Freeman Co., New York to also show the phosphatase step). Note The diagram of fructose in this figure (red) is rotated so that its anomeric carbon atom (C2) lies to the right of the ring structure instead of the left as in a conventional diagram. Because of the rotation, it is not obvious that the fructose bond in sucrose is in the (3-anomeric configuration. Only the glucose bond is in the a-anomeric configuration. The conventional diagrams of glucose and fructose alone and in sucrose are illustrated in Fig. 15.6.
A disaccharide is formed when two monosaccharides become joined by a glycosidic bond. The bond may be an a- or (3-bond depending on the configuration of the anomeric carbon atom involved in the bond. Usually the anomeric carbon atom of only one of the two monosaccharides is involved in the bond so that the disaccharide still has one free aldehyde or ketone group and is still reducing. However, in sucrose both anomeric carbon atoms are bonded together so that sucrose is a nonreducing disaccharide. [Pg.267]

Hestrin, Feingold, and Avigad (195a) found that the levansucrase enzyme system of Aerohacter levanicum which utilizes the D-fructose moiety of sucrose, forming a polysaccharide (levan) and D-glucose, possesses a complementary property of catalyzing the reversible transfer of the D-fruc-tosyl unit of jS-D-fructofuranosyl aldosides of different configurations to the anomeric carbon position of an aldose. [Pg.530]

Invertase - catalysed hydrolysis of sucrose can occur to the extent of 99% in 1 min with retention of configuration at both anomeric centres. [Pg.25]

See other pages where Sucrose anomeric configuration is mentioned: [Pg.10]    [Pg.239]    [Pg.10]    [Pg.18]    [Pg.654]    [Pg.141]    [Pg.211]    [Pg.213]    [Pg.210]    [Pg.259]    [Pg.319]    [Pg.283]    [Pg.9]    [Pg.159]    [Pg.972]    [Pg.221]    [Pg.107]    [Pg.484]    [Pg.393]    [Pg.246]    [Pg.595]    [Pg.19]    [Pg.17]    [Pg.292]    [Pg.271]    [Pg.16]    [Pg.462]    [Pg.839]    [Pg.315]    [Pg.246]    [Pg.93]    [Pg.302]    [Pg.475]    [Pg.111]    [Pg.27]    [Pg.15]    [Pg.1103]   
See also in sourсe #XX -- [ Pg.505 ]



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