2.3.4- Tri-O-acetyl-a-D-xylopyranose

C9H20O4S2 D-Ribose diethyl dithioacetal (DRETAC)316 CuH15C107 Tri-0-acetyl-/ -D-xylopyranosyl chloride (TACXYP)317 CuH1605 2,3,4-Tri-O-acetyl-a-D-xylopyranose (TAXYLP)318 C12H220,i -HoO 6-O-a-D-Galactopyranosyl-a.fl-D-glucopyranose, monohydrate (MELIBM03)319... 

In the aldopentose series, 2,3,4-tri-O-acetyl-a-D-xylopyranose afforded the corresponding unsaturated 1,5-lactone by oxidation - elimination. Likewise, hepta-O-acetylcellobiose gave, upon oxidation (184), the product of -elimination at the reducing end. 2,3,4,6-Tetra-O-benzoyl-D-gluco- and D-mannopyranoses were not oxidized by the same reagents. 

Acetylated and Benzoylated Derivatives of Sugars.—1,2,3,5-Tetra-O-acetyl-jS-D-ribofuranose, 3-0-acetyl-jS-L-arabinofuranose 1,2,5-orthobenzoate, (Z)-l-O-acetyl-2,3 4,5-di-0-isopropylidene-D-e/ y/Aw- and -D-/Areo-pent-l-enitol, 2,3,4-tri-O-benzoyl-jS-D-xylopyranosyl chloride, 2,3,4-tri-0-acetyl-j9-D-xyIopyranosyI azide, 1,3,4-tri-0-acetyl-2-deoxy-2-fluoro-a-D-xylopyranose, 1,2,3,4-tetra-O-acetyl-a-D-Iyxopyranose, 2,3,4,6-tetra-0-acetyl-a -D-glucopyranosyl bromide, 3,4,6-tri-0-acetyl-l,2-0-(l-cyanoethyIidene)-a-D-glucopyranose, 3,4,6-tri-O-acetyl-)S-D-mannopyranose l,2-(methyi orthoacetate), 2,3-di-0-acetyI-l,6-anhydro-jS-D-galactopyranose, 2,3,4,6-tetra-0-acetyl-j8-D-galactopyranosyl cyanide, 1,2,3,4,6-penta-O-acetyl-a-D-idopyranose, 1,4,5-tri-0-acetyl-2,3-0-isopropyIidene-)S-D-fructopyranose, and 2,3,4-tri-O-acetyl-a-L-rhamnopyrano-syl and 2,3,4,6-tetra-O-acetyl-a-D-mannopyranosyl chlorides. ... 

The telomerization of butadiene (1) with protected pentoses has been particularly studied using 2,3,4-tri-(9-acetyl-D-xylopyranose (5) [21] and 2,3,4-tri-O-benzyl-p-D-arabinofuranose (8) [22] as the telogens, in a 50-mL stainless steel autoclave... 

It is not requisite that the anion eliminated in the step 19 to 20 be a hydroxyl ion, because acid hydrolysis of 5-amino-5-deoxy-l,2-0-isopropylidene - 3 - O - (methylsulfonyl )-a- D -xylofuranose likewise yields 3-pyridinol (21). On subjection to acid hydrolytic conditions which remove the 2V-acetyl group, such N-acetyl derivatives as 5-acetamido-5-deoxy-a-D-xylopyranose (see p. 167) are immediately transformed, through 17, into 3-pyridinol (21). Furthermore, acid hydrolysis of methyl 5-acetamido-5-deoxy-2,3,4-tri-0-methyl-a-D-... 

Free Sugars and Simple Derivatives Thereof. — Partially deuteriated j8-L-arabino-pyranose and a-L-xylopyranose (n.d. refinement), 1,2-6>-cyclohexylidene- and l,2-O-isopropylidene-0 -D-glucofuranose 3,5,6-phosphites, 5-O-acetyl-l,2 3,4-di-O-isopropylidene-a-D-galactoseptanose, 3,4,6-tri-O-acetyl-l, 2-0-(R )-ethyl-... 

Cl 1H12N8O11, 2-Methyl-5- N-nitrocarboxamido)-1-(2, 3, 5 -tri-0-nit-ro- -D-ribofuranosyl)imidazol-4-carboxamide, 46B, 433 Cl1H13NO7, p-Nitrophenyl- -D-xylopyranoside, 42B, 319 Cl1H15BrN20n, Arabinose p-bromophenylhydrazone, 27, 790 Cl 1H1 sBrN20i, Ribose-p-bromophenylhydrazone, 29, 489 C11H15CIO7, 2,3,4-Tri-O-acetyl- -D-xylopyranosyl chloride, 40B, 391 1,3,4-Tri-0-acetyl-2-desoxy-2-fluoro-a-D-xylopyranose,... 

Chloroacetyl groups (see Vol. 4, p. 38) have been used as temporary protecting groups in the synthesis of a number of o-xylose derivatives, including 1,2,3-tri-0-acetyl-p-D-xylopyranose and 1,2-di-O-acetyl-a- and -P-D-xylofuranose. The hydroxy-groups of nucleosides have been protected as crotonic and other substituted acrylic esters, which can be readily removed with hydrazine under mild conditions. The claim that acetylation of D-ribose with hot acetic anhydride in the presence of barium carbonate gives only 1,2,3,5-tetra-O-acetyl-P-D-ribofuran-ose has been refuted, since n.m.r. spectroscopy has shown D-ribo-furanose and -pyranose tetra-acetates are formed. ... 

Copolymerization of l,4-anhydro-2,3-di-0-(to7-butyldimethylsilyl)-a-D-xylopy-ranose (39) with l,4-anhydro-2,3-di-0-benzyl-a-i>xylopyranose (27), followed by desilylation with tetrabutylammonium fluoride gave a partially benzylated sterero-regular (l -->5)-a-D-xylofuranan. [37] A branched polymer (40) was obtained when it was glycosylated with 3,4,6-tri-0-acetyl-P-D-mannose l,2-(methyl orthoacetate). Debenzylation of the polymer having D-mannosyl branches with sodium in liquid ammonia yielded (1 — 5)-a-i>xylofuranans having 2- or 3-O-a-D-mannopyranosyl branches. 

A facile new synthesis of 4-0-allyl-D-xylopyranose has been reported, and 1,2,4-tri-O-acetyl-3-0-allyl-L-fucopyranose has been prepared in a number of steps from D-arabinose. A number of 2-,3-,4- and 6-0-(n-alkyl)-D-glucoses have been prepared by standard means (via alkylation of... 

Hepta-A c 1,2,3-Tri-O-acetyl-4-O-(2,3,4,6-tetra-O-acetyl-p-D-glucopyra-nosyl)-D-xylopyranose C25H340i7 606.533 Cryst. (MezCO). Mp 154-157°. [a]g -18.2 (c, 0.98 in CHCI3). 

The synthesis of 5-deoxy-5[(R)- and (S)- methylphosphinyl]-a, -D-manno- and L-gulo-pyranoses, as well as o-l,2,4-tri-0-acetyl-5-deoxy-5[(R)- and (S)-ethylphosphinyl]-3-0-methyl-D-xylopyranoses have been reported and the 5-deoxy-3-0-methyl-5 phenylphosphinyl-L-fucopyranoses have been prepared as the first P-in-the-ring analogues of L-fucose. The 5,6-dideoxy-5-C-dimethoxyphosphinyl-D-ay/o-hex-5-enofuranoses have also been described. ... 

These crystal-structure analyses are concerned with the following molecules o-D-glucopyranose monohydrate/ D-xylopyranose/ methyl yS-D-xylopyranoside, di-jS-n-fructopyranose-strontium chloride trihydrate, cellobiose (independent determination), D-glucaric acid, D-galactonic acid, methyl a-D-lyxofuranoside, /3-D-lyxopyranose, methyl 3,4,6-tri-0 - acetyl - 2 - (chloromercuri) - 2 - deoxy - j3 - d - glucopyranoside, D-glu-copyranosyl (potassium sodium phosphate) tetrahydrate," and methyl 6-bromo-6-deoxy-a-D-galactopyranoside. ... 

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