Glucose chloride

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. ... 

Carry out this preparation precisely as described for the a-compound, but instead of zinc chloride add 2 5 g. of anhydrous powdered sodium acetate (preparation, p. 116) to the acetic anhydride. When this mixture has been heated on the water-bath for 5 minutes, and the greater part of the acetate has dissolved, add the 5 g. of powdered glucose. After heating for I hour, pour into cold water as before. The viscous oil crystallises more readily than that obtained in the preparation of the a-compound. Filter the solid material at the pump, breaking up any lumps as before, wash thoroughly with water and drain. (Yield of crude product, io o-io 5 g.). Recrystallise from rectified spirit until the pure -pentacetylglucose is obtained as colourless crystals, m.p- 130-131° again two recrystallisations are usually sufficient for this purpose. 

Salicin is a colourless crystalline substance, soluble in water. It does not reduce Fehling s solution nor does it give a coloration with ferric chloride. On hydrolysis with emulsin, glucose and salicyl alcohol are produced the former reduces Fehling s solution and the latter gives a violet coloration with ferric chloride. 

Conversion of (3- into a-glucose penta-acetate. Add 0-5 g. of anhydrous zinc chloride rapidly to 25 ml. of acetic anhydride in a 200 ml. round-bottomed flask, attach a reflux condenser, and heat on a boiling water bath for 5-10 minutes to dissolve the solid. Then add 5 g. of the pure P glucose penta-acetate, and heat on a water bath for 30 minutes. Pour the hot solution into 250 ml. of ice water, and stir vigorously in order to induce crystaUisation of the oily drops. Filter the solid at the pump, wash with cold water, and recrystaUise from methylated spirit or from methyl alcohol. Pure a-glucose penta-acetate, m.p. 110-111°, will be obtained. Confirm its identity by a mixed m.p. determination. 

Acetates. Complete acetylation of all the hydroxyl groups is desirable in order to avoid mixtures. In some cases, the completely acetylated sugars may be obtained in the a- and p-forms depending upon the catalyst, e.g., zinc chloride or sodium acetate, that is employed in the acetylation. The experimental details for acetylation may be easily adapted from those already given for a- and p-glucose penta-acetates (Section 111,137). 

Benzoates. Benzoyl chloride has a very limited application as a reagent in the sugar series, but it is useful for the preparation of a crystal line derivative of glucose and of fructose. 

In a 50-100 ml. conical flask place a solution of 0 -5 g. of glucose in 5 ml. of water, 12-15 ml. of 10 per cent, sodium hydroxide solution and 1 ml. of benzoyl chloride, cork tightly, and shake until the odour of benzoyl chloride has disappeared and a crystalline (frequently sticky) soUd has separated. Filter oflF the solid, wash it with a Uttle water, and recrystaUise it from ethyl or n-butyl alcohol. (If the product is sticky, it should be removed, and spread on a porous tile before recrystaUisation.) Glucose pentabenzoate has m.p. 179°. Fructose pentabenzoate, m.p. 78-79°, may be similarly prepared. 

A Acylsarcosinates. Sodium A/-lautoylsarcosinate [7631-98-3] is a good soap-like surfactant. Table 4 gives trade names and properties. The amido group in the hydrophobe chain lessens the interaction with hardness ions. A/-Acylosarcosinates have been used in dentifrices (qv) where they ate claimed to inactivate enzymes that convert glucose to lactic acid in the mouth (57). They ate prepared from a fatty acid chloride and satcosine ... 

A fermentation such as that of Pseudomonas dentrificans typicaby requires 3—6 days. A submerged culture is employed with glucose, comsteep Hquor and/or yeast extract, and a cobalt source (nitrate or chloride). Other minerals may be required for optimal growth. pH control at 6—7 is usuaby required and is achieved by ammonium or calcium salts. Under most conditions, adequate 5,6-dimethylben2imida2ole is produced in the fermentation. However, in some circumstances, supplementation maybe required. 

Interestingly, phase-transfer catalysts including crown ethers have been used to promote enantioselective variations of Darzens condensation. Toke and coworkers showed that the novel 15-crown-5 catalyst derived from d-glucose 33 could promote the condensation between acetyl chloride 31 and benzaldehyde to give the epoxide in 49% yield and 71% A modified cinchoninium bromide was shown to act as an effective phase transfer catalyst for the transformation as well. ... 

The complex thioamide lolrestat (8) is an inhibitor of aldose reductase. This enzyme catalyzes the reduction of glucose to sorbitol. The enzyme is not very active, but in diabetic individuals where blood glucose levels can. spike to quite high levels in tissues where insulin is not required for glucose uptake (nerve, kidney, retina and lens) sorbitol is formed by the action of aldose reductase and contributes to diabetic complications very prominent among which are eye problems (diabetic retinopathy). Tolrestat is intended for oral administration to prevent this. One of its syntheses proceeds by conversion of 6-methoxy-5-(trifluoroniethyl)naphthalene-l-carboxyl-ic acid (6) to its acid chloride followed by carboxamide formation (7) with methyl N-methyl sarcosinate. Reaction of amide 7 with phosphorous pentasulfide produces the methyl ester thioamide which, on treatment with KOH, hydrolyzes to tolrestat (8) 2[. 

Two liters of an aqueous medium consisting of glucose 3%, starch 2%, soybean meal 3% and sodium chloride 1 5% were equally divided and introduced into twenty 500-ml Erlenmeyer flasks, adjusted to pH 6, sterilized at 120°C for 30 minutes, inoculated with Streptamyces griseoverticillatus var. tuberacticus N6-130 end then rotatively shakecultured broth containing 2,360 mcg/ml of tuberactinomycin-N. 

As described in U.S. Patent 2,929,763, methandrostenolone may be made by a fermentation route. 2 g of sodium nitrate, 1 g of primary potassium orthophosphate, 0.5 g of magnesium sulfate heptahydrate, 0.5 g of potassium chloride, 50 g of glucose and 1 g of Difco yeast extract are dissolved in one liter of tap water, brought to pH 5 by addition of a sodium hydroxide solution and sterilized. The resulting nutrient solution is inoculated with 50 cc of a 4-day-old shaking culture of Didyniel/a lycopersici and shaken for 48 hours at 27 C, whereby the culture becomes well developed. 

Sterile agar slants are prepared using the Streptomyces sporulation medium of Hickey and Tresner, J. Bact., vol. 64, pages 891-892 (1952). Four of these slants are inoculated with lyophilized spores of Streptomyces antibioticus NRRL 3238, incubated at 28°C for 7 days or until aerial spore growth is well-advanced, and then stored at 5°C. The spores from the four slants are suspended in 40 ml of 0.1% sterile sodium heptadecyl sulfate solution. A nutrient medium having the following composition is then prepared 2.0% glucose monohydrate 1.0% soybean meal, solvent extracted, 44% protein 0.5% animal peptone (Wilson s protopeptone 159) 0.2% ammonium chloride 0.5% sodium chloride 0.25% calcium carbonate and water to make 100%. 

A derivatization with acid chlorides is also possible. Amino acids can be derivatized with 9-fluorenylmethyl chloroformate (FMOC) and separated on a CSP with X-cyclodextrin (ChiraDex gamma ), a cyclic oligosaccharide which consists of eight glucose units. 

Deoxy-D-jcylo hexose 6-(dihydrogen phosphate) (21) has also been synthesized (2) the reaction sequence makes use of 3-deoxy l 2,5 6-di-O-isopropylidene D-galactofuranose (16), a compound that can be easily prepared from D-glucose (2, 60). The mono-isopropylidene derivative (17) formed by partial hydrolysis of the di-ketal is converted into the 6-tosylate (18) by reaction with one molar equivalent of p-toluenesulfonyl chloride. From this the epoxide (19) is formed by reaction with sodium methoxide. Treatment of the anhydro sugar with an aqueous solution of disodium hydrogen phosphate (26) leads to the 6-phosphate (20)... 

Metal halide salts other than sodium iodide have been used sparsely to prepare halodeoxy sugars from sulfonate esters. Lithium chloride (107) and lithium bromide (33) have found limited application. Potassium fluoride (dihydrate) in absolute methanol has been used (51, 52) to introduce fluorine atoms in terminal positions of various D-glucose derivatives. The reaction is conducted in sealed tube systems and requires... 

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