How are the following pairs of carbohydrates, shown in a Fischer projection, related to each other? Are they structural isomers, enantiomers, diastereomers, or epimers? Identify each as the D- or L-isomer.
(b)

Question

How are the following pairs of carbohydrates, shown in a Fischer projection, related to each other? Are they structural isomers, enantiomers, diastereomers, or epimers? Identify each as the D- or L-isomer.
(b)

(b) Fischer projections of two carbohydrate pairs, illustrating their relationships as isomers or enantiomers.

Accepted Answer

Welcome back, everyone examine the f projections of the monos Se Rs shown below. What is their relationship? Are they structural isomers dias in an tumor or epimer? Additionally classify each as either D or L iser. So first of all, we want to check whether or not these two structures have the same molecular formula. We can see that they have all the same atoms, 123456 carbons, 123456 oxygens and 12 hydrogens, 123456789, 1011, 12. So they have the same molecular formula, meaning possibly they are structural isomers. So structural isomers si while they cannot be structural isomers, because they do not differ in the connectivity of atoms, we can see that every carbon has exactly same atoms bond. What about the asteria? Well, those are stereo isomers that are not in Antium. So what we want to do is simply draw a mirror plane and we want to see if these structures can represent a reflection of one another. Well, essentially we can see that the a age groups at the third carl position. Well, they are indeed a reflection of one another but the others aren't. Right. So essentially we can see that for example, carbon number two, it has the same configuration because a wage is on the same side. Carbon number three has the same configuration because the age groups are on the same side. Carbon three doesn't carbon four, I'm sorry. Right. Carbon five. Well, it also has the same configuration because the H is on the same side. So these two structures only differ by one configuration of a chiral atom, meaning they are dias theem. However, it is not our final answer. We have to recall that epimer. Well, it is a specific case in which the two structures differ by the configuration of one carbon only. And this is the case here, we can see that all of these atoms have the same configuration, specifically carbons 23 and five, they have the same configuration, but carbon number 1234, right, that specific carbon has opposite configurations. And this gives us only one carbon with a different configuration, which means that the two structures are first of all omers. And now to assign ad or L configuration, we have to consider the final chiral position. And that would be the farthest chiral carbon from Carboni. So we are starting with an aldehyde, we're moving down and we noticed that according to the official projection, that would be carbon number five. Now d means that a wage is on the right L means that O is on the left for that specific carbon. And we notice that a wage in each case is on the right side of the Fisher projection. Meaning both of these are D isomers. So we can just state D and D for each. And that will be our final answer. The two structures are ers and they both have ad configuration, they are both D isomers. Thank you for watching.

How are the following pairs of carbohydrates, shown in a Fischer projection, related to each other? Are they structural isomers, enantiomers, diastereomers, or epimers? Identify each as the D- or L-isomer.
(b)

Verified video answer for a similar problem:

Key Concepts

Structural Isomers

Stereoisomers

Epimers

How are the following pairs of carbohydrates, shown in a Fischer projection, related to each other? Are they structural isomers, enantiomers, diastereomers, or epimers? Identify each as the D- or L-isomer. (b)

Verified video answer for a similar problem:

Key Concepts

Structural Isomers

Stereoisomers

Epimers

How are the following pairs of carbohydrates, shown in a Fischer projection, related to each other? Are they structural isomers, enantiomers, diastereomers, or epimers? Identify each as the D- or L-isomer.
(b)