Methyl arabinoside

Arabinosecarboxylic acid, I, 3, 4 Arabinoside. See also Arabinofuranoside and Arabinopyranoside, L-Arabinoside, methyl 2,3-dimethyl-, II, 245... 

Fig. 7.—Predicted (- -) and Fragment (—) Circular Dichroism Spectra /3-L-Arabinose Calculated from (a) a-D-Xylose, and (b) Methyl /3-L-Aiabinoside a-L-Arabinose Calculated from (c) j3-D-Xylose, and (d) Average Calculated for /3-L-Arabinose Methyl a-L-Arabinoside Calculated from (e) Methyl /3-D-Xyloside, and (f) Methyl /3-L-Arabinoside. (Redrawn from Ref. 6.)...

Toikka, M. Sipila, J. Teleman, A. Brunow, G. Lignin-carbohydrate model compounds. Formation of lignin-methyl arabinoside and lignin-methyl galactoside benzyl ethers via quinone methide intermediates. J. Chem. Soc., Perkin Trans. 1998, 1, 3813-3818. 

Gossypetin 7-methyl ether 1145. 3-Arabinoside 3-Rhamnoside 3-Galactoside 8-Glucoside 3-Rutinoside... 

Chart V summarizes the reactions of 2,3- and 3,4-anhydropento-pyranosides. Buchanan and coworkers have shown144 that the methyl 2,3-anhydro-a(and /3)-lyxosides, and 3,4-anhydro-/3-L-arabinoside adopt that half-chair conformation (5H0) in which the anomeric meth-oxyl group is axially attached this indicates the importance of the ano-... 

Honeyman147 reported the synthesis of methyl 2,3-anhydro-/3-L-lyxopyranoside, and claimed that, on alkaline hydrolysis, this gives a 2 1 ratio of L-xyloside L-arabinoside, but these results could not be substantiated by Buchanan and R. Fletcher,68 who recorded different constants for the epoxide and for the disulfonic ester claimed147 to be the starting material for its synthesis. The same epoxide has been synthesized by Reist and coworkers,160 and its properties are in agreement with Buchanan and Fletcher s results. Ethyl or methyl 3,4-anhydro-/3-L-ribopyranoside undergoes substitution at C-4 in all the reactions thus far studied. Neither half-chair conformation would seem to be clearly favored, but the specificity observed can be rationalized by considering the steric and polar interactions that may arise in the transition state substitution at C-3 in conformation 58 would involve marked interactions between the nucleophile and... 

The configuration of the products was established by periodate oxidation of the D compound, and reduction of the resulting dialdehyde to an optically active diol whose sign and magnitude of optical rotation ([a] ° +2.5° in water) correspond to that of the diol ([a]n° 46.8° in water) obtained by similar treatment of methyl a-L-arabinopyrano-side. The bis(p-nitrobenzoates) of the two diols exhibited similar relationships. Hence, it appears likely that the configuration at C-2 of the anhydride is the same as that at C-l of the L-arabinoside. The cis relationship of the hydroxyl groups was retained from the arabinal started with. 

Along the same line, on the other hand, methyl 2,3-anhydro -L-riboflido gives rise to a mixture of methyl 3-deeoxy-/S-L-xyloside and methyl 2-desoxy-0-n-arabinoside (Eq. 371), of which the 3-desoxy sugar is the principal constituent.1248 Analogous results were obtained separately in the d-series by other investigator 1 2 using lithium aluminum hydride. 

Allerton and Overend180 showed that the action of hydrochloric acid on LXIV leads to a slightly better yield (18.4%) of the methyl 2-halogeno-2-desoxy-D-arabinoside, but these methods have no value for the large scale synthesis of 2-desoxy-D-ribose. 

J. S. Burton, W. G. Overend, and N. R. Williams, Branched-chain-sugars. Part II. The introduction of branching into methyl 3,4-0-isopropylidene-/ -l-arabinoside and the synthesis of L-hamamelose, J. Chem. Soc., (1965) 3433-3445. 

Di-O-methyl-D-galactose, 4-O-methyl-D-mannose, methyl /3-L-arabinoside 0.32... 

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