Acetone glucose

Procedure. Add D-glucose (1.00 g, 5.55 mmol) to a solution of iodine (0.30 g, 1.18 mmol) in acetone (50 ml) and stir the suspension at room temperature for 4 h. After this time the sugar will have dissolved completely and the reaction will have gone to completion by TLC analysis (19 1, chloroform/methanol). Quench the reaction by the addition of dilute sodium thiosulfate solution to render the reaction mixture colourless, then remove the acetone in vacuo. Transfer the aqueous solution to a separatory funnel and extract with chloroform (3 X 20 ml), then wash the combined organic layers with distilled water (100 ml), dry (Na2S04) and remove solvents in vacuo to afford the crude product. Recrystallisation (diethyl ether/petrol) affords di-acetone glucose as colourless crystals (1.09 g, 80%). Mp 109-110 °C [ ]d = -13.5 (c 1.0, chloroform) NMR (CDCI3) 1.32, 1.37, 1.45 and 1.50 (4 X s, 4 X CH3,... 

After extensive experimentation, the Duthaler-Haffner variant was chosen, which involves two di-acetone glucose ligands 31 as stereo inductors at the titanium ion. The reagent was able to overrule the substrate control of this reaction and resulted in a 5.5 1 ratio for the desired diastereomer 30 at — 100°C, in roughly 70% yield. 

Most current industrial vitamin C production is based on the efficient second synthesis developed by Reichstein and Grbssner in 1934 (15). Various attempts to develop a superior, more economical L-ascorbic acid process have been reported since 1934. These approaches, which have met with htde success, ate summarized in Crawford s comprehensive review (46). Currently, all chemical syntheses of vitamin C involve modifications of the Reichstein and Grbssner approach (Fig. 5). In the first step, D-glucose (4) is catalytically (Ni-catalyst) hydrogenated to D-sorbitol (20). Oxidation to L-sotbose (21) occurs microhiologicaRy with The isolated L-sotbose is reacted with acetone and sulfuric acid to yield 2,3 4,6 diacetone-L-sorbose,... 

Acetalation. As polyhydroxy compounds, carbohydrates react with aldehydes and ketones to form cycHc acetals (1,13). Examples are the reaction of D-glucose with acetone and a protic or Lewis acid catalyst to form l,2 5,6-di-0-isoprop5lidene-a-D-glucofuranose [582-52-5] and its reaction with benzaldehyde to form 4,6-0-benzyhdene-D-glucopyranose [25152-90-3]. The 4,6-0-(l-carboxyethyhdine) group (related to pymvic acid) occurs naturally in some polysaccharides. 

Urine testing can play a role in identifying ketone excretion in patients prone to ketoacidosis. If urine testing is done, it is usually recommended tiiat the nurse use the second voided specimen (ie, fresh urine collected 30 minutes after the initial voiding) to check glucose or acetone levels, ratiier than die first specimen obtained. 

A crude protein extract has been prepared by acetone precipitation on a three days old culture supernatant of the SCPP strain on Pg glc medium. In order to estimate the effect of glucose on PG activity, these protein extracts were deposited as dots on solid Pg glc medium. 

S (2)-hydroxy-3-butenenitrile from acrolein and HCN trans hydrocyanation using, for instance, acetone cyanohydrin Hydrolysis of nitriles to amides, e.g. acrylonitrile to acrylamide Isomerization of glucose to fructose Esterifications and transesterifications Interesterify positions 1 and 3 of natural glycerides Oxidation of glucose to gluconic acid, glycolic acid to glyoxalic acid... 

Batch reactor Production of acetone and butanol from glucose Clostridium acetobutylicum 129... 

What is described as a domino Knoevenagel-hetero-Diels-Alder reaction , involving the reaction of the glucose-derived aldehyde 93 with a 1,3-dicarbonyl compound in presence of either proline or ethylenediammonium acetate, leads to the doubly annulated 5 6 6-fused compound 94 (Scheme 30) <2004S1150>. If the dicarbonyl compound is Meldmm s acid, however, the sequence is completed by spontaneous elimination of acetone and carbon dioxide from the Diels-Alder adduct, to give compound 95 <2005ASC1353>. 

Bayne, Fewster and Mitchell16 prepared VII by the method of Stacey and Turton, and recorded physical properties closely agreeing with those reported by Maurer.66 The compound was clearly related to D-glucosone, prepared from D-glucose phenylosazone and by direct oxidation, since, on treatment with dry acetone containing concentrated sulfuric acid, it gave crystalline tri-0-isopropylidene-(2-hydroxy-D-arabmo-hexose). 7... 

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