Monosaccharides, methyl

Hricovini, M., Malkina, O. L., Bizik, F., Nagy, L. T., Malkin, V. G., 1997, Calculation of NMR Chemical Shifts and Spin-Spin Coupling Constants in the Monosaccharide Methyl [1 ]) xylopyTniiosidc Using a Density Functional Theory Approach , J. Phys. Chem. A, 101, 9756. 

A solution structure of a simple methylated monosaccharide, methyl /3-D-xylopyranoside (I) in a weakly aligned medium, was recently elucidated based on 30 RDCs (15 DHH, 4 Dch, and 11 BDCH).153 These were... 

Compound 230 can also be converted to the monosaccharides methyl a-L-mycaminoside (232) in three steps and methyl a-L-oleandroside (233) in four steps. 

Li, H. Giles, K. Bendiak, B. Kaplan, K. Siems, W.E. HiU, H.H., Resolving structural isomers of monosaccharide methyl glycosides using drift tube and traveling wave ion mobihty mass spectrometry. Ana/. Chem. 2012, 84, 3231—3239. 

Reaction of hydrazine 165 with a number of monosaccharides give hydrazones 166 (92BCJ546). Their acetylations gave peracetyl derivatives 167. The same reactions were extended to the /V-methyl and the 7-methyl derivatives of 165 (93 JPROO). That compounds 166 exist as open-chain structures was based on a 2D NMR study (93MI1) (Scheme 35). 

Note. A monosaccharide with a terminal methyl group is named as a deoxy sugar, not as a C-methyl derivative. 

The glycosyl-residue compositions of the three purified fractions (Table 1) were very similar with a predominance of galacturonic acid, rhamnose and arabinose. The presence in the three purified fractions of the rare monosaccharides characteristic of RG-II (e.g. 2-( -methyl-L-fucose, 2-O-methyl-D-xylose, apiose, Kdo, Dha and aceric acid) was confirmed by GC-CIMS analysis. The molar ratios corresponded approximately to the known structure of the RG-II molecule (Figure 1) and to previously published data for RG-II from sycamore [26], rice [4], arabidospis leaves [8] and Pectinol [12]. 

The monosaccharide composition of all the samples was determined by GLC analysis of the trimethylsilyl methyl glycoside derivatives [1]. 

Supplement 1941 1-161 Derivatives. Methyl alcohol, 273. Ethyl alcohol, 292. Ethyl ether, 314. Glycerol, 502. Carbonyl Compounds Aldehydes, Ketones, Ketencs and Derivatives. Formaldehyde, 558. Acetaldehyde, 635. Acetone, 635. Ketene, 724. Hydroxy-Carbonyl Compounds Aldehyde-Alcohols, Ketone-Alcohols, Monosaccharides and Derivatives. Glycolaldehyde, 817. Aldol, 824. Pentoses, 858. Hexoses, 878. 

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