Glucose labeled

Deoxy-2-[18F]fluoro-D-glucose (labelled) or (2fl)-2-deoxy-2-[18F]fluoro-D-arab/no-hexose... 

The comparative biochemistry of glycolysis has been studied very effectively using D-glucose labeled in specific positions with C14. The distribution of C14 in the key intermediates and end products, compared with those... 

On the other hand, 13C-NMR spectroscopy not only allows the simultaneous and separate detection of signals from different compounds, but also within different atoms in a given molecule. For example, carbon-13 from glucose labeled at the Cl (or C6) position is incorporated via the PDH reaction into the C2 of acetyl-CoA, and subsequently into the C4 of a-ketoglutarate (Fig. 31-9), which labels the... 

FIGURE 31 -10 Cerebral amino acids and carbohydrates incorporate 13C label from infused glucose. The top panel shows a 13C NMR spectrum obtained from a gray-matter-rich volume in the human head. (From reference [141].) The right panel shows label incorporation into brain glycogen and glucose in humans. (From reference [142].) The stack plot illustrates the rate of label incorporation into many compounds and carbons in the rat brain. (From reference [ 143].) In all studies, glucose labeled at the 1 or 6 position was administered intravenously. 

Scheme 14 Biosynthesis of the C5 unit of thiamin from isotopically labelled hexoses. Label from D-[l-14C]glucose and D-[l-uC]fructose label C-4 exclusively D-[2-14C]glucose labels C-4 and C-4 equally D-[6-14C]glucose labels C-4 (16% of 14C incorporated the precise location of the remaining 14C was not determined) d-[6-D2]glucose gives rise to both [4 -D2]- and [7-D2]-thiamin...

The glucose-glycine reaction has therefore been reinvestigated using glucose labelled with 90 % at C-1. The behavior of a few potential intermediates under similar reaction conditions has also been studied. 

O. Gabriel and G. Ashwell, Biological mechanisms involved in the formation of deoxysugars. I. Preparation of thymidine diphosphate glucose labelled specifically in carbon 3, J. Biol. Chem., 240 (1965) 4123-4127. 

Scheme 9.—Positions of the Carbon-14 label in L-Streptose (25) from D-Glucose Labelled at C-l (A), C-3 ( ), or C-6 ( ).

Scheme 13.—Biosynthetic Conversion of D-Glucose into Streptidine by way of Keto-sci/iio-inositol 32 (compare Scheme 12), with C-6 of D-Glucose Labelling C-6 of Streptidine by Path A. (Path B is analogous to the pathway found for formation of deoxystreptamine by S. fradiae.)...

In the presence of unlabeled D-glucose, there was no significant incorporation of labeled acetate, pyruvate, and formate into shikimic acid. Variously labeled D-glucose gave the distribution of activities shown in Fig. 1. Only D-glucose labeled in Cl, C2, equally in C3 and C4, or C6 (abbreviated G-1, G-2, G-3,4, and so on) were available for trial. The large deficiencies which occurred in Cl and C5 of shikimate were, therefore, assigned to G-5. The relative contributions of G-3 and G-4 were unknown, but could be... 

Tracing carbon atoms I. Glucose labeled with at C-1 is incubated with the glycolytic enzymes and necessary cofactors. 

Tracing glucose. Glucose labeled with at C-6 is added to a solution containing the enzymes and cofactors of the oxidative phase of the pentose phosphate pathway. What is the fate of the radioactive label ... 

---