In glucose

An ethyl carbonate, prepared and cleaved by conditions similar to those described for a methyl carbonate, was used to protect a hydroxyl group in glucose. ... 

Butylethylidene and 1-phenylethylidene ketals were prepared selectively from the C4-C6, 1,3-diol in glucose by an acid-catalyzed transketalization reaction [e.g., Me3CC(OMe)2CH3, TsOH/DMF, 24 h, 79% yield PhC(OMe)2Me, TsOH, DMF, 24 h, 90% yield, respectively]. They are cleaved by acidic hydrolysis AcOH, 20°, 90 min, 100% yield, and AcOH, 20°, 3 days, 100% yield, respectively. Ozonolysis of the /-butylmethylidene ketal affords hydroxy ester, albeit with poor regiocontrol, but a more sterically differentiated derivative may give better selectivity, as was observed with the ethylidene ketal. ... 

Photosynthesis uses many of the same enzyme-driven steps found in glucose metabolism, only in... 

Identify each pair of relationships among the -OH groups in glucose (red-blue, red-green, red-black, blue-green, blue-black, green-black) as cis or trails. 

One of the later steps in glucose biosynthesis is the isomerization of fructose 6-phosphate to glucose 6-phosphate. Propose a mechanism, using acid or base catalysis as needed. 

Figure 23.10 Mechanisms of type I and type II aldolase reactions in glucose biosynthesis.

Problem 29.9 Which carbon atoms in glucose end up as — CH3 carbons in acetyl CoA Which carbons end up as C02 ... 

Carbon from the substrate glucose is converted into the carbon of the cells, phenylalanine, carbon dioxide and byproducts. Carbon balance calculations thus give us more understanding of the amount of carbon in glucose used for cell mass production, for synthesis of the wanted produd, maintenance energy and byproduct formation. 

Usual dose schedules of streptozotocin involve 500 mg/m2 i.v. during five consecutive days. The major toxicity is renal tubular damage. Treatment of metastatic insulinomas may result in the release of insulin from the tumor and subsequent hypoglycemic coma. Less severe toxicities include diarrhea, anemia, and mild alterations in glucose tolerance or liver function tests. 

Extrapolations are always subject to error, but fortunately the contribution to the entropy resulting from the extrapolation is a small part of the total. In glucose, for example, S g = 219.2 0.4 J-K -moF1, but the entropy contribution at 10 K obtained from the Debye extrapolation is only 0.28 J-K 1-mol 1. Well-designed cryogenic calorimeters are able to produce Cp measurements of high accuracy hence, the Third Law entropy obtained from the Cp measurements can also be of high accuracy. 

Sometimes it is important to know the three-dimensional structure of a molecule. In glucose, for example,... 

Figure 19-5. Variation in glucose phosphorylating activity of hexokinase and glucokinase with increase of blood glucose concentration. The for glucose of hexokinase is 0.05 mmol/L and of glucokinase is 10 mmol/L.

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