D and L glucose

[m25]

How do D and L glucose look like in a ring structure? Is the below diagram correct?

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[Cawolf]

Yes, they are enantiomers as shown.

 

[m25]

Yes, they are enantiomers as shown.

Oh, I always thought D and l glucose are epimers since they only differ in one of their stereocenters, but they are actually enantiomers?

 

[Cawolf]

They are enantiomers.

You may be confused because the normal Fischer projection shows only one difference (Carbon 4 substituent direction), but D and L specifically refers to an enantiomeric pair.

 

[NextStepTutor_1]

@Cawolf is correct. D and L sugars are enantiomers, not epimers. You may have thought that those only refer to the quintessential carbon (the last chiral carbon), but the 2 are enantiomers. Check it out:
http://mcat-review.org/carbohydrates.php

This is a fantastic site, btw, and I strongly recommend using it.