Alginic acid methylated

L-Gulose readily forms an anhydride, and in a study on alginic acid, methylated L-guloses were isolated as their anhydrides.88 Other anhydro sugars, such as 3,6-anhydro-L-galactose and its 2-methyl ether, may be found in algae (see, for example, Ref. 412), and, under certain circumstances, 2,3,6-tri-O-methyl-D-galactose may form an anhydride.571... 

Treatment of alginic acid methyl ester with AA-dimethylbiguanidine afforded a 5-triazinyl derivative having C-6 of the hexuronic acid residues incorporated into... 

Pectins are generally classed according to their ester content as high methoxyl pectins (>50% of the carboxyl groups esterified) or low methoxyl pectins (<50% of carboxyl groups esterified) (pectic acid, methyl ester [9049-34-1]). Low methoxyl pectins, like algins, require calcium for gelation. 

This compound, previously prepared174 in low yield from alginic acid, has been synthesized128 from 61 by oxidation at C-2, and stereospecific reduction of the intermediate methyl 5-0-benzyl-/3-D-nrab-ino-2-hexulofuranosidurono-6,3-lactone. Hydrogenolysis of the 5-0-benzyl group yielded the title compound in a superior yield. 

Proof of the structure of the uronic acid was obtained by Hirst, Jones and Jones,46 who isolated the methyl glycoside methyl ester by methyla-tion of the products from the graded methanolysis of alginic acid. The tri-O-methyl-D-mannuronic acid was converted to the diamide of 2,3,4-tri-O-methyl-D-mannaric acid, which had previously been prepared from... 

Sulfated and methylated xylogalactans of die agar group and alginic acids Complex sulfated galactans (DL-hybrids)... 

The Structure of Alginic Acid. Part V. Isolation and Unambiguous Characterization of Some Hydrolysis Products of the Methylated Polysaccharide, Sir Edmund Hirst and D. A. Rees, J. Chem. Soc., 1182 (1965). 

Alginic acid, 279, 281, 286, 314, 322 esters of, 279, 314 salts of, 275, 279, 280, 286 Allopyranoside, methyl 2-acetamido-2-deoxy-a-D-, 3-methyl ethers, 202 Allose, 2-amino-2-deoxy-D-, methyl ethers of, 202, 214... 

Poly (maleic anhydride-alt-1-octadecene). See Octadecene/MA copolymer Poly (maleic anhydride-methyl vinyl ether). See PVM/MA copolymer Polymannuronic acid. See Alginic acid Polymeg 650] Poiymeg 1000, Polymeg ... 

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