I can't quite remember what exactly makes a glucose molecule D or L. When in the Fisher projection but not in ring form, a glucose molecule has a chain of 6 carbons. #1 carbon is the CHO and #6 C is the CH2OH. Each carbon in between has a OH and a H attached to it. For the D-glucose, the OH is: #2 - right; #3 - left; #4 - right; #5 - right. I know that for L-glucose, the OH on one of the carbons is reversed (i.e. it goes from on the right to on the left). I can't remember which carbon it flips on: #2 or #5.
2007-02-12 03:28:23 · 3 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
D and L glucose are complete mirror images of each other. So, each OH that is on the right in the Fisher projection of D glucose will be on the left in L glucose.
The D and L families are defined by the orientation of the OH on the chiral carbon farthest from the carbonyl group. So, for hexoses, if the OH on carbon #5 is on the right it is a D sugar, if it's on the left, it is an L sugar.
2007-02-12 03:40:58 · answer #1 · answered by hcbiochem 7 · 2⤊ 0⤋
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What is the difference between D and L glucose?
I can't quite remember what exactly makes a glucose molecule D or L. When in the Fisher projection but not in ring form, a glucose molecule has a chain of 6 carbons. #1 carbon is the CHO and #6 C is the CH2OH. Each carbon in between has a OH and a H attached to it. For the D-glucose, the OH...
2015-08-14 00:11:33 · answer #2 · answered by Leonie 1 · 0⤊ 0⤋
what occurs in biology. L-glucose has the wrong shape to interact with the enzymes that process D-glucose, just like left-hand nuts not being able to fit onto right-hand threads. All the other differences follow from this. The physical and chemical properties are identical, except that those involving a difference between left and right are in opposite directions (e.g. rotating the plane of polarised light).
2016-03-16 02:31:30 · answer #3 · answered by Anonymous · 0⤊ 0⤋
In Emil Fisher Projection-Aldoses-when the structure is co-planar with the plane of the paper,in the penaltimate carbon atom of Tetrose,pentose,Hexose-if the OH group is on the rightside(of the observer) it is D-series and OH on the left,it is L-series, irrespctive of its optical rotation
2007-02-12 04:42:08 · answer #4 · answered by ssrvj 7 · 0⤊ 0⤋