I was searching for the Haworth projection of sucrose and I got this image from wikipedia (and much of the internet).
(wikipedia link: https://en.m.wikipedia.org/wiki/Sucrose).enter image description here

But isn't it wrong!?
The image shows a (#1Carbon to #5C) linkage of glucose to fructose respectively.
What i think the image is showing:
(edited wikipedia image) enter image description here

But it should show (#1C to #2C) linkage of glucose to fructose respectively. Should it not be like this image: enter image description here

  • $\begingroup$ Your fructose in the second picture is numbered incorrectly. #2 is #5 and #5 is #2. The correct C2 is a ketal carbon, a masked ketone. Fructose is a 2-ketose. $\endgroup$
    – user55119
    Nov 18 '21 at 22:24
  • $\begingroup$ This may be of help: chemistry.stackexchange.com/questions/87178/… $\endgroup$
    – user55119
    Nov 18 '21 at 22:26

Those are the same, just shown in a different conformation and a different view.

enter image description here

As user55119 points out in the comments, the numbering went awry (in fructose, #2 is the anomeric carbon in the ring form, or the carbonyl carbon in the linear form).

Sucrose has no reducing "ends", which it would have if fructose would link via the #5 carbon.

If you look at one of the crystal structures of sucrose, you will find that the rings are not parallel but rather perpendicular, allowing some nice hydrogen bonds:

enter image description here

  • $\begingroup$ Beside the pure chemical perspective of this answer, it is an eye-catching showcase about advantages of vector-based images in formats like .svg. $\endgroup$
    – Buttonwood
    Nov 18 '21 at 22:55
  • $\begingroup$ @Buttonwood The provided figure was pixel-based, so I had to remove the background to make it transparent... $\endgroup$ Nov 18 '21 at 23:03
  • $\begingroup$ Great animation, much thanks. Which software did you use btw. $\endgroup$ Nov 19 '21 at 3:51
  • $\begingroup$ @KarstenTheis Oh, but it has so much similarity to the depiction of sucrose on top of the property box in the English edition of Wikipedia, which is available as .svg here ... $\endgroup$
    – Buttonwood
    Nov 19 '21 at 6:54
  • 1
    $\begingroup$ @JustCurious I used commercial software I happen to have, PowerPoint for the first figure, and Camtasia to capture the screen and turn it into an animated gif. The second figure is of SUCROS01 was rendered with the open software Jmol. $\endgroup$ Nov 19 '21 at 11:29

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