2-Methylglyceric acid

Fig. 7 -31. Peeling and stopping reactions of polysaccharides (Sjostrom, 1977). R = polysaccharide chain and R = CH2OH (cellulose and glucomannans) or H (xylan). Cellulose and glucomannans (R = CH2OH) (1) 3-Deoxyhexonic acid end groups (metasaccharinic acid), (2) 2-C-methylglyceric acid end groups, (3) 3-deoxy-2-C-hydroxymethylpentonic acid (glucoisosaccharinic acid), (4) 2-hydroxypropanoic acid (lactic acid), and (5) 3,4-dideoxypentonic acid (2,5-dihydroxypentanoic acid). Xylan (R = H) (3) 3-Deoxy-2-C-hydroxymethyltetronic acid (xyloisosaccharinic acid), (4) 2-hydroxypropanoic acid (lactic acid), and (5) 2-hydroxybutanoic acid. 1977. TAPPI. Reprinted from Tappi 60(9), p. 152, with permission.

One other important method of preparation had been used by two groups of workers it involved the direct oxidation of the crotonic acids by means of barium permanganate. Fittig and Kochs obtained by this process an anhydrous, crystalline, racemic dihydroxybutanoic acid (IVab) of m.p. 74-75° from crotonic acid, and a liquid dihydroxybutanoic acid (Illab) from isocrotonic acid. In 1904, Morrell and Hanson resolved the jS-methylglyceric acid (Illab) of Fittig and Kochs with quinidine and... 

Figure 6.12 Stopping the peeling reaction by formation of 3-0-cellulose glycosides of 2-C-methylglyceric acids.

Edney, E. O., Kleindienst, T. E., Jaoui, M., Lewandowski, M., Offenberg. J. H., Wang, W., and Claeys, M. (2005) Formation of 2-methyl tetrols and 2-methylglyceric acid in secondary organic aerosol from laboratory irradiated isoprene/NOx/S02/air mixtures and their detection in ambient PM2 5 samples collected in the eastern United States, Atmos. Environ. 39, 5281-5289. 

OH HO- isoprene tetrol 2-methylglyceric acid (and related compounds)... 

Angliceric Acid (Anglycaric acid, 1 2-di-methylglyceric add, 1 2-dikydroxyA tnethyl. butyric acid) "... 

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