D-Arabinofuranoside

Only one site for periodic acid cleavage in methyl a-D-arabinofuranoside... 

Parker, R. J., Priester, E. R., and Sieber, S. M. (1982). Comparison of lymphatic uptake metabolism, excretion, and biodistribution of free and liposome-entrapped (l cjcytosine beta-D-arabinofuranoside following intraperitoneal administration in rats, Drug. Me tab. Dispos., 10, 40-46. 

From their kinetic results Bishop and collaborators >8) calculated the velocity constants of the furanoside anomerisations of their seven aldoses (Table 1), and rationalised them in terms of ring conformations and group interactions. Thus, for example, in the extreme cases methyl a-D-arabinofuranoside (4), having the fewest non-bonded steric interactions, is the most stable pentofuranoside, while methyl p-o-lyxofurano-side (5), having the least stable ring, reacts most rapidly. 

In the case of the methyl D-fructofuranosides, there is a relationship to the D-arabinofuranosides, with a different type of C-l, C-2 interaction. Here, the hydrogen atom on C-l has been replaced by a hydroxymethyl group, and the difference in the C-2 interactions with the C-3 hydroxyl group should be small for the anomers the effect of the aglycon group (OMe) and the hydroxymethyl group will probably be similar. 

For the D-fructofuranosides, there is apparently little difference between interactions of either the aglycon methyl group or the hydroxymethyl group (on C-2) with the C-3 hydroxyl group the anomers are formed in approximately equal yields. The high yields obtained indicate the conformational stability of the D-fructofuranoside structure, which is very similar to that of the D-arabinofuranosides. 

Whereas ethyl l-thio-d-D-arabinofuranoside cannot be prepared directly, the 5-O-benzoyl diethyl dithioacetal gave 38% of ethyl 5-O-benzoyl-l-thio-0-D-arabinofuranoside, which was debenzoylated to the desired product. The 5-benzoate of ethyl 1-thio-a-D-ribofuranoside was similarly prepared.88 Two other compounds, ethyl 2-acetamido-2-deoxy-l-thio-/3-L-arabino-furanoside72 and ethyl 2-acetamido-2-deoxy-l-thio-a-D-xylofuranoside,73 were prepared from the corresponding d-galacto and d-gluco analogs by periodate oxidation, and subsequent borohydride reduction of the product. 

It was shown that methyl 2,3-anhydro-/l-D-ribofuranoside (180) forms an equilibrium mixture with methyl 3,5- anhy dr o -/T i)- x y 1 oI uranoside (181), whereas the corresponding a anomer 182 gives in sodium methoxide solution the major product of epoxide-ring opening, namely methyl 2-0-methyl-a-D-arabinofuranoside (183).523,524... 

L. Fiume, A. Mattioli, C. Busi, G. Spinosa, and T. Wieland, Conjugates of adenine 9-P-D-arabinofuranoside monophosphate (ara-AMP) with lactosaminated homologous albumin are not immunogenic in the mouse, Experientia 38 1087-1089 (1982). 

The use of the p-methoxybenzyhdene acetal tethered intramolecular aglycone delivery was extended to polymer-supported oligosaccharide synthesis [77]. The method also proved to be successful in the synthesis of other difficult linkages, such as (3-D-fructofuranosides [78], (3-D-arabinofuranosides [79-81] and a-D-fucofuranosides [82]. 

Callam, C S, Lowary, T L, Synthesis and conformational investigation of methyl 4a-carba-D-arabinofuranosides, J. Org. Chem., 66, 8961-8972, 2001. 

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