5-Mannitol

In addition to enzymatic hydrolysis (see Section 5.8.1), inulin can be hydrolyzed chemically and subsequently dehydrated to yield hydroxymethylfurfural (van Dam et al., 1986), a key industrial chemical (Gretz et al., 1993 Fuchs, 1987 Kunz, 1993 Makkee et al., 1985 van Dam et al., 1986). Likewise, catalytic hydrogenation of D-fructose yields D-mannitol and D-sorbitol mixtures from which mannitol can be removed via crystallization (Fuchs, 1987). 

D-Mannitol has a diverse range of industrial applications. It is a nonhydroscopic, low-calorie, noncariogenic sweetener utilized by the food industry as well as a feedstock for the synthesis of other compounds. For example, mannitol can be oxidized at the 3 or 4 position to form two molecules of glyceraldehyde or glyceric acid, which can be used as building blocks for other compounds (Heinen et al., 2001 Makkee et al., 1985 van Bekkum and Verraest, 1996). Mannitol is formed from inulin via hydrolysis followed by catalytic hydrogenation. This yields mannitol and sorbitol from which the mannitol can be readily crystallized (Fuchs, 1987). Currently mannitol is primarily synthesized from starch. 

Biology and Chemistry of Jerusalem Artichoke Helianthus tuberosus L. 

The ions at m/z 361 and 73 were considered as complementary products, resulting from fissions between C-l-C-2 or C-5-C-6 and retaining the charge at either of the breakdown products. The fragments at m/z 289 and 145 were suggested to be generated in a similar way, which necessitates the cleavage of C-2-C-3 or C-4-C-5 bonds, while the ion 

Specifically the stereoisomer mannitol. Chromatographic separation was still required to unambiguously identify and isolate the target analyte from analogues such as alhtol, altritol, sorbitol, galactitol, and iditol (see Chapter 6). 

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In the presence of glycerol or mannitol (polyhydroxo compounds) boric acid behaves as a much stronger acid the reaction can be represented as ... 

Benzoic acid Succinic. anhydride Hexacetyl mannitol ... 

Removal of bases from mixtures of bases and neutral compounds. The procedure here is essentially the same as in (i) above. The base is retained by the column. Use a solution of 0 05 g. of benzylamine and o-i g. of mannitol in 100 ml. of water. The effluent contains only mannitol. 

For complete acetylation of polyhydric compounds, such as glucose (p. 141) and mannitol (p. I42), even undiluted acetic anhydride is insufficient, and a catalyst must also be employed. In such cases, the addition of zinc chloride or anhydrous sodium acetate to the acetic anhydride usually induces complete acetylation. ... 

Mannitol, CH,0H(CH0Hi4CH40H, is a hexahydric alcohol obtained by the reduction of mannose. Since ring formation does not occur in mannitol, the hexacetyl derivative can exist in only one form, and therefore either zinc chloride or sodium acetate can be used as a catalyst for the acetylation. 

Required Mannitol, 5 g. acetic anhydride, 30 ml. zinc chloride, ca, 0-5 g. 

Take approximately 0 5 g. of the finely powdered mannitol, using either a weighing bottle, or else weighing directly in the flask A as before. Heat on the water-bath for 60 minutes. During the titration with the NaOH solution, a fine precipitation of the hexacetyl-mannitol may occur, but will not affect the titration. The results are excellent. 

Continue precisely as for triacetin, but since hexacetyl-mannitol (p. 142) is a crystalline compound, weigh out i o-i 2 g. of the finely powdered substance, either from a weighing-bottle, or by direct weighing in the flask A. The results are excellent. 

J The hexa.acetyl derivative, m.p. 121°, may be prepared as follows. Boil under reflux 1 part of mannitol with 5 parts by weight of acetic anhydride and 1 part of anhydrous sodium acetate or with a little anhydrous zinc chloride for 15-20 minutes, pour into excess of water, stir the mixture until the oil has solidifled, and then recrystallise from methylated spirit. 

Another name for glucitol obtained by reduction of d glucose is sorbitol it is used as a sweetener especially in special diets required to be low in sugar Reduction of D fructose yields a mixture of glucitol and mannitol corresponding to the two possi ble configurations at the newly generated chirality center at C 2... 

Br , citrate, CE, CN , E, NH3, SCN , S20 , thiourea, thioglycolic acid, diethyldithiocarba-mate, thiosemicarbazide, bis(2-hydroxyethyl)dithiocarbamate Acetate, acetylacetone, BE4, citrate, C20 , EDTA, E , formate, 8-hydroxyquinoline-5-sul-fonic acid, mannitol, 2,3-mercaptopropanol, OH , salicylate, sulfosalicylate, tartrate, triethanolamine, tiron... 

Acetylacetone, ascorbic acid, citrate, C20j, EDTA, F , H2O2, hydrazine, mannitol, NagP30io, NH2OH HCI, oxidation to molybdate, 8CN , tartrate, tiron, triphosphate... 

Ti Ascorbic acid, citrate, F , gluconate, H2O2, mannitol, NagP30io, OH , SOJ , sulfosalicylic... 

Boric acid F, glycol, mannitol, tartrate, and other hydroxy acids... 

Spectral searching and stripping in the analysis of a mixture of mannitol and cocaine hydrochloride, (a) IR spectrum for the mixture (b) Library IR spectrum of mannitol (c) Result of subtracting mannitol s IR spectrum from that of the mixture ... 

INFRARED TECHNOLOGY AND RAMAN SPECTKOSCOPY - INFRARED TECHNOLOGY] (Vol 14) -mannitol in [SUGARALCOHOLS] (Vol 23)... 

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