Skip to main content
Chemistry

You are not logged in. Your edit will be placed in a queue until it is peer reviewed.

We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.

3
  • 2
    $\begingroup$ Levorotatory is lower case "l" or a minus sign, not "L". All natural amino acids, save, glycine, are of the Fischer/Rosanoff designation L. Dextrorotatory means "d or +". Most, if not all, natural sugars are of the Fischer/Rosanoff designation D. The carbon that gives this assignment happens to be R. D and L are configurations; d and l are optical rotations. Search "carbohydrate configurations" in Search on Chemistry at the top of the page. $\endgroup$
    – user55119
    Commented Nov 16, 2020 at 22:51
  • 1
    $\begingroup$ So, the answer to your question is "yes". Dextrorotatory sugars are "d" or "+". But a sugar has no chirality. Chirality is not a property of a molecule. Only carbon atoms have a chirality, and this chirality is R or S. $\endgroup$
    – Maurice
    Commented Nov 17, 2020 at 10:18
  • 2
    $\begingroup$ I would say chirality is a property of the molecule rather than just a specific center. A molecule is chiral if it has no improper rotation symmetry elements, which can be caused by point center of chirality like a carbon atom, but also from axial chirality (e.g. a helical structure). I guess you mean we can't assign R or S labels to a whole molecule, but I would refer to these labels as "configurations" rather than "chiralities". $\endgroup$
    – Tyberius ♦
    Commented Dec 3, 2021 at 17:42