Rhamnofuranoside, methyl 2,3-0-isopropylidene

Gives a 90-95 % yield of the corresponding glyooseen-5,0 (together with some of the expected methyl 2,3-O-isopropylidene-L-rhamnofuranoside). 

Methyl-L-rhamnose has been synthesized from the reducing product, 2,3-isopropylidene-L-rhamnofuranose (LIV), which is obtained by the condensation of L-rhamnose with acetone in the presence of sulfuric acid and copper sulfate. Methylation with silver oxide and methyl iodide in the presence of sodium sulfate gave methyl 2,3-isopropylidene-5-methyl-/ -L-rhamnofuranoside (LV), from which was obtained by hydrolysis 5-methyl-L-rhamnose (LVI).62... 

Preparation. 6-Deoxy-D-allose may be obtained through the series of configurational inversions that occur on treatment of methyl 2,3-0-isopropylidene-5-0-p-tolylsulfonyl-L-rhamnofuranoside with sodium methoxide.163... 

Levene and Compton found that p-toluenesulfonation of methyl 2,3-0-isopropylidene-a, 3-L-rhamnofuranoside results in the isolation of both the 4-0-p-tolylsulfonyl pyranoside and the 5-0-p-tolylsulfonyl furanoside. Some doubt exists as to whether the original acetal contained some pyranoside, or whether the ring change occurred during the p-toluenesulfonation. 

O-Isopropylidene, 5-benzoyl Methyl 5-0-benzoyl-2,3-0-isopropylidene-a-D-rhamnofuranoside... 

Me glycoside, 2,3-isopropylidene, S-Ac Methyl 5-S-acetyl-2,3-0-isopropylidene-5-thio-x-L-rhamnofuranoside C12H20O5S 276.353 Cryst. (hexane). Mp 48°. [ ]d -69.9 (c, 1 in CHCI3). 

Methyl 4-0-acetyl-2,3-0-isopropylidene-a-L-rhamnopyranoside, M-207 Methyl 5-5-acetyI-2,3-0-isopropylidene-5-thio-a-D-lyxofuranoside, T-80 Methyl 5-5-acetyI-2,3-0-isopropylidene-5-thio-a-L-rhamnofuranoside, T-88 Methyl 4-0-acetyI-2,3-0-isopropylidene-l-thio-p-D-xylopyranoside, T-98 Methyl 2-0-acetyI-4,6-0-isopropylidene-3-0-tosyl-a-D-gulopyranoside, M-194... 

Methyl 2,3-0-isopropylidene-5-0-mesyl-a-D-rhamnofuranoside, M-206 Methyl 2,3-0-isopropylidene-4-0-mesyl-a-D-rhamnopyranoside, M-207 Methyl 2,3-0-isopropylidene-4-0-mesyl-a-L-rhamnopyranoside, M-207 Methyl 3,5-0-isopropylidene-2-0-mesyl-a-D-xylofuranoside, M-216 Methyl 2,3-0-isopropylidene-6-0-methyl-p-L-dlofuranoside, M-148 Methyl 2,3-0-isopropylidene-3"-methyl-D-apio-p-D-furanoside, A-785 Methyl 3,4-0-isopropylidene-2-0-methyl-p-D-arabinopyranoside, M-153... 

Methyl 3,5-0-isopropylidene-2-O-methyl-a-D-xylofuranoside, M-216 Methyl 3,5-0-isopropylidene-2-O-methyl-p-D-xylofuranoside, M-216 Methyl 2,3-0-isopropylidene-p-D-r 6o-pentodialdo-l,4-furanoside, P-35 Methyl 3,5-0-isopropylidene-p-D-tAreo-pentofuranoside, P-45 Methyl 3,5-0 -isopropylidene-a-D-tAreo -pentofuranosid-2-ulose, P-45 Methyl 3,4-0 -isopropylidene- -i -erythro -pentopyranosid-2-ulose, P-42 Methyl 3,4-0 -isopropylidene-a-L-erytAro -pentopyranosid-2-ulose, P-42 Methyl 3,4-0 -isopropylidene-p-L-erytAro -pentopyranosid-2-ulose, P-42 Methyl 2,3-0 -isopropylidene-p-L-erytAro -pentopyranosid-4-ulose, P-44 Methyl 2,3-0 -isopropylidene-p-DL-erytAro -pentopyranosid-4-ulose, P-44 Methyl 2,3-0-isopropylidene-a-L-rhamnofuranoside, M-206 Methyl 2,3-0-isopropylidene-a-o-rhamnopyranoside, M-207 Methyl 2,3-0-isopropylidene-a-L-rhamnopyranoside, M-207 Methyl 2,3-0-isopropylidene-p-D-ribofuranoside, 1-74 Methyl 2,3-0-isopropylidene-p-L-ribofuranoside, 1-74 Methyl 2,3-0-isopropylidene-5-0-a-D-ribofuranosyl-P-D-ribofuranoside, R-119... 

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