Arabinopyranoside methyl 2-0-benzoyl-3,4-0-benzylidene

Another internal acetal, methyl 2-0-benzoyl-3,4-0-benzylidene-/ -D-arabinopyranoside 103 (84), behaves in an analogous manner, except that the isomeric 4-bromo (104) and 3-bromo (105) benzoate derivatives are formed in a ratio of 1 1. The identity of 104 (l-xylo) can be deduced from its mode of formation from a presumed benzoxonium ion (106)... 

The first example in the pyranoid series was afforded153 by methyl 2-0-benzoyl-3,4-0-benzylidene-j8-D-arabinopyranoside (92), which gave the corresponding benzoxonium ion (93) this ion was shown to be in equilibrium158 with its regio- and stereo-isomer 94, the latter... 

Methyl 2-0-benzoyl-a-D-arabinofuranoside, M-152 Methyl 2-0-benzoyl-3-0-benzyl-a-D-arabinofuranoside, M-152 Methyl 3-0-benzoyl-5-0-benzyl-2-deoxy-2-fluoro-p-D-xylofuranoside, D-118 Methyl 2-0-benzoyl-4,6-0-benzylidene-a-D-allopyranoside, M-155 Methyl 2-0-benzoyl-4,6-0-benzylidene-a-D-altropyranoside, M-156 Methyl 3-0-benzoyl-4,6-0-benzylidene-a-D-altropyranoside, M-156 Methyl 2-0-benzoyl-3,4-0-benzylidene-p-L-arabinopyranoside, M-153 Methyl 2-0-benzoyl-4,6-0-benzylidene-3-bromo-3-deoxy-a-D-altropyranoside, B-59... 

Methyl 2-0-benzoyl-a-D-arabinofiiraiioside, M-152 Methyl 2-0-benzoyl-3-0-benzyl-a-i>ajabmofiiraiioside, M-152 Methyl 2-0-benzoyl-3,4-0-benzylidene-p-L-ajabinopyraiioside, M-153 Methyl 5-0-benzoyl-3-bromo-3-deoxy-p-i>arabmofiiranoside, B-63 Methyl 5-0-benzoyl-3-deoxy-3-iodo-a-i>ajabmofiiranoside, D-250 Methyl 4-0-benzoyl-2-deoxy-2-iodo-p-L-arabinopyranoside, D-249 Methyl 2-0-benzoyl-3,4-0-ethylidene-p-L-arabinopyranoside, M-153 Methyl 2-0-benzoyl-3,4-0-isopropylidene-p-L-ajabinopyraiioside, M-197 Methyl 2-O-benzyl-p-D-arabmofuranoside, M-152 Methyl 2-0-benzyl-p-L-arabinopyranoside, M-153 Methyl 3,4-O-benzylidene-p-L-arabinopyranoside, M-153 Methyl 3,4-0-benzylidene-2-0-tosyl-p-L-arabinopyranoside, M-153 Methyl 2-0-benzyl-3,4-0-isopropylidene-p-L-ajabinopyranoside, M-197 Methyl 2-bromo-2-deoxy- -D-arabinopyranoside, B-62 Methyl 3-bromo-3-deoxy-P-D-arabinopyranoside, B-63 Methyl 2-chloro-2-deoxy-a-D-arabinofuranoside, C-74 Methyl 2-chloro-2-deoxy-P-D-arabinofuranoside, C-74 Methyl 4-chloro-4-deoxy-P-D-arabinopyranoside, C-75 Methyl 3,5-di-0-acetyl-2-bromo-2-deoxy-a-D-arabinofuranoside, B-62 Methyl 3,5-di-0-acetyl-2-bromo-2-deoxy-P-D-arabinofuranoside, B-62 Methyl 3,5-di-0-acetyl-2-chloro-2-deoxy-a-D-arabinofuranoside, C-74 Methyl 3,5-di-0-acetyl-2-chloro-2-deoxy-P-D-arabinofuranoside, C-74 Methyl 3.4-di-0-acetyl-2-chloro-2-deoxy-a-D-arabinopyranoside, C-74 Methyl 3,4-di-0-acetyl-2-deoxy-2-iodo-a-D-arabinopyranoside, D-249 Methyl 3,4-di-0-acetyl-2-deoxy-2-iodo-a-L-arabinopyranoside, D-249 Methyl 3,5-di-0-acetyl-2-0-methyl-a-D-arabinofuranoside, M-152 Methyl 3,5-di-0-acetyl-2-0-methyl-p-D-arabinofuranoside, M-152 Methyl 3,4-di-0-acetyl-2-0-methyl-p-L-arabinopyranoside, M-153 Methyl 2,3-di-0-acetyl-4-0-methyl-a-DL-arabinopyranoside, M-153 Methyl 2,3-di-O-benzoyl-p-L-arabinopyranoside, M-153 Methyl 3,5-di-0-benzoyl-2-bromo-2-deoxy-p-D-arabinofuranoside, B-62 Methyl 2,4-di-0-benzoyl-3-bromo-3-deoxy-p-D-arabinopyranoside, B-63 Methyl 2,3-di-0-benzoyl-5-0-tosyl-a-L-arabinofuranoside, M-152 Methyl 2,3-di-O-benzyl-a-L-arabinofuranoside, M-152 Methyl 2,3-di-O-benzyl-P-L-arabinofuranoside, M-152 Methyl 3,5-di-0-benzyl-2-chloro-2-deoxy-a-D-arabinofuranoside, C-74 Methyl 3,4-di-0-benzyl-2-deoxy-2-C-(tosylcarbamoyl)-a-L-arabinopyranoside, C-8... 

Methyl 4-0-benzoyl-2-deoxy-2-iodo-p-L-arabinopyranoside, D-249 Methyl 3-0-benzyl-4,6-0-benzylidene-2-chloro-2-deoxy-a-D-glucopyranoside, C-85... 

Methyl 3-0-a-L-arabinofuranosyl-p-D-xylopyranoside, A-823 Methyl 2-0-a-L-arabinopyranosyl-a-L-arabinopyranoside, 9CI, A-834 Methyl 2-0-a-L-arabinopyranosyl-p-L-arabinopyranoside, 9CI, A-834 Methyl 4-0-p-L-arabinopyranosyl-a-L-arabinopyranoside, 9CI, A-840 Methyl 4-0-p-L-arabinopyranosyl-p-L-arabinopyranoside, 9CI, A-840 Methyl 4-0-a-L-arabinopyranosyl-a-L-arabinopyranoside, A-836 Methyl 4-0-a-L-arabinopyranosyl-p-L-arabinopyranoside, A-836 Methyl 3-0 -benzoyl-4,6-benzylidene-2-0 -(2,3,4,6-tetra-0-acetyI-p-i> glucopyranosyl)- p-D-allopyranoside, G-277 Methyl 4-0-(4,6-0-benzylidene-p-D-allopyranosyl)-p-D-allopyraiioside, A-84... 

Treatment of methyl 2-0-benzoyl-3,4-0-benzylidene-P-D-arabinopyranoside with triphenylmethylium tetrafluoroborate in acetonitrile gave an equilibrium mixture of the benzoxonium ions (96) and (97), which reacted with chloride or iodide ions to give(98) and (99) in the ratio of 6 1 (X = Cl) or 1 2 (X = I), signifying differences in the reactivities of (96) and (97) towards different halide ions. The... 

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