Amylose carbon

Kim OK, Je JT, Baldwin JW, Kooi S, Pehrsson PE, Buckley LJ (2003) Solubilization of singlewall carbon nanotubes by supramolecular encapsulation of helical amylose. J. Am. Chem. Soc. 125 4426 f427. 

Xie YH, Soh AK (2005) Investigation of non-covalent association of single-walled carbon nanotube with amylose by molecular dynamics simulation. Mater. Lett. 59 971-975. 

Carbonates, diaryl, reactions with cyclohepta-amylose, 23 240 Carbon dioxide adsorption, 21 44 on chromia, 20 27 on gallium-doped NiO, 22 247-251 on nickel catalysts, 22 87-96 dissociative, 22 93-96... 

Brass and Bender (1973) have recently studied reaction of bis ( -nitrophenyl) carbonate with cyclohepta-amylose. Michaelis-Menten kinetics were observed, and two equivalents of p-nitrophenol released. Release of the first equivalent of />-nitrophenol is rate-determining, the second one being released in a fast step. The latter... 

The isomeric polysaccharides amylose (a component of starch) and cellulose also show the significance of stereoisomerism on polymer properties. Cellulose and amylose have the structures shown in Fig. 8-8. (Amylopectin, the other component of starch, has the same structure as amylose except that it is branched at carbon 6.) Both are polymers of glucose in which the... 

On the basis of researches devoted to the products of paitial or total hydrolytic breakdown of methylated starch, the chain of a-D-anhydroglucose is thought to constitute the main element of the amylose and amylopectin molecules. These units are combined as in maltose, i.e. by means of a-glucosidic linkages formed between the carbon atoms 1 and 4 ... 

Neutralization of a potassium hydroxide adduct of amylose with gaseous carbon dioxide leads to a potassium hydrogen carbonate adduct. This type of reaction, which is rapid in a moist atmosphere, could possibly be used in the preparation of bicarbonate adducts of other carbohydrates. 

Starch can be vinylated with acetylene in the presence of potassium hydroxide in an aqueous tetrahydrofuran medium.1 1 The mechanism possibly involves the addition of the potassio derivative of starch across the carbon-carbon triple bond of acetylene, with subsequent hydrolysis of the organometallic intermediate to give the vinyl ether. Such a mechanism has been postulated for the formation of vinyl ethers from monohydric alcohols and acetylene, in the presence of an alkali metal base as catalyst.1 2 The vinylation of amylose is very similar to the vinylation of amylopectin, except for the relative ratio of mono- to di-substitution. With amylopectin, the proportion of disubstitution is greater. In both starches, the hydroxyl group on C-2 is slightly more reactive than the hydroxyl group on C-6 there is little substitution at the hydroxyl group on C-3. 

Balmer et al. [60] separated the two enantiomers of omeprazole on three different stationary phases with immobilized protein, viz, Chiral-AGP with a-1 acid glycoprotein, Ultron ES-OVM with ovomucoid, and BSA-DSC with BSA cross-linked into 3-aminopropyl silica using N-suc-cinimidyl carbonate. The mobile phase (1 ml/min) was phosphate buffer solution with 3—10% 2-propanol as the organic modifier. The enantiomers of omeprazole were separated on Chiralpak AD, an amylose-based chiral stationary phase, with ethanol-hexane (1 4) as mobile phase (1 ml/min). 

C-CP-MAS NMR produces a broad resonance with a chemical shift of 31.2 ppm,129 a characteristic of mid-chain methylene carbons of fatty acids in the V-amylose complex. The results showed that up to 43% of amylose in non-waxy rice starch, 33% in oat starch, and 22% in normal maize and wheat starch granules are complexed with lipids at a single helical conformation, and the remaining amylose is free of lipids and is in a random coil conformation.212 Up to 60% of apparent amylose in waxy barley starch is complexed with lipids.212... 

---