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Organic Chemistry 2

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Moderate

Stereochemistry of Triose Phosphate Isomerase

ORGO2-BQVTQB

The triose phosphate isomerase-catalyzed interconversion of dihydroxyacetone phosphate (DHAP) and glyceraldehyde-3-phosphate (G-3-P) is notable because it represents an enzymatic process that is diffusion controlled.

In part, the rapidity of this enzymatic process can be explained by the stereospecificity of the isomerization process that occurs in the enzyme active site.

Specifically, when DHAP is labeled with deuterium ($^2H$), an isotope of hydrogen, at carbon-1, it can be shown that the pro-R hydrogen is selectively removed by the enzyme to afford G-3-P as its 2-deuterio isomer (see scheme below).

Created for Albert.io. Copyright 2016. All rights reserved.

Given this information, determine which of the following isotopically-labeled isomers of DHAP would produce G-3-P as its deuterioaldehyde isomer.

A

(R)-3-deuterio-glyceraldehyde-3-phosphate

B

(S)-3-deuterio-glyceraldehyde-3-phosphate

C

(S)-1-deuterio-glyceraldehyde-3-phosphate

D

(R)-1-deuterio-glyceraldehyde-3-phosphate