The haworth structures of lactose and sucrose is

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My question is regarding the glyosidic linkage, in lactose it is represented as a zig zag and in sucrose it is a "V". What does that mean. Also, in sucrose why is the the glyosidic linkage displaced down w.r.t the compound

  • $\begingroup$ The link in lactose structure is beta (up position)-1(1-position around the ring)-4(glucose's 4-position around its ring, in which the OH is down for glucose). The link in sucrose is alpha (down)-1(glucose's 1-position)-2(fructose's 2-position which is at the down position because fructose is "facing" the glucose unit and it is upside down). $\endgroup$ – z1273 Mar 10 at 18:35
  • $\begingroup$ Haworth structures are cumbersome to draw in this regard. The bridging oxygens are attached directly to the rings and not to CH2 groups as the "zig-zag" and "V" might imply. $\endgroup$ – user55119 Mar 10 at 23:42

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