Penta-0-acetyl-3-deoxy-3-C

Fig. 9.—Proton Magnetic Resonance Spectrum of l,2,3, 4,6-Penta-0-acetyl-3-deoxy-3-C-(hydroxymethyl)-a-D-glucose in CDCI3 at 100 MHz.

The large coupling-constants of H-2, H-3, and H-4 support the ailerons orientation of these hydrogen atoms, and, therefore, (56) and (58) are penta-0-acetyl-3-deoxy-3-C-(hydroxymethyI)-a-D-glucopyr-anose and penta-0-acetyl-3-deoxy-3-C-(hydroxymethyl)-a-D-glucopyr-anose-2,3, 3 -da. 

Treatment of penta-0-acetyl-3-deoxy-3-C-(hydroxymethyl)-a-D-glu-copyranose (56) with hydrogen bromide in glacial acetic acid readily afforded the corresponding, branched-chain glycosyl bromide. Condensation of the latter with dithyminylmercury yielded a compound that is presumed (from its infrared and nuclear magnetic resonance spectra) to be the branched-chain nucleoside (62),... 

Fig. 4. — Mass Spectrum79 of l,2,3,4,6-Penta-0-acetyl-5-deoxy-5-C-[(R)-ethylphosphinyl]-/ -D-glucopyraiiose (134). 

Penta-Ac, Me ester Methyl (2,4,6,7,8-penta-0 acetyl 3 deoxy D manno-oct-2-ulofuranosid)onate [73154-87-71 C19H26O13 462.407 Cryst. (Et20/hexane). Mp 123-125°. Wd +4 (c, 1 in MeOH). 

Penta-O-Ac 2,3,4,5,6-Penta-O-acetyl-I-amino-l-deoxy-D-glucitol CisHzjNOio 391.374 Cryst. (EtOH aq.) (as hydrochloride). Mp 178-180° (hydrochloride). [a]o +1-5 (c, 0.7 in H2O) (hydrochloride). 

Penta-Ac 6-Acetamido-1,2,3,4-tetra-O-acetyl-6-deoxy-p-D-glucopyranose C16H23NO10 389.358 Mp 114-120°. [ag +9.9 (c, 0.8 in CHCI3). 

The rates of displacement of the sulphonate group by azide ion in DMF at 110 °C have been measured for a series of toluene-p-sulphonyl and p-bromo-benzenesulphonyl derivatives of 3-0-methyl-cA/ra-inositol and 4-0-methyl-tf//< -inositol in these compounds, the arylsulphonate group was located at position 4 (or 3), and the substituents at positions 1,2, 5, and 6 were isopropylidene, acetyl, methyl, and cyclic carbonate. All of the resulting azides (except the unreactive penta-O-methyl-c/j/ra derivative) could be converted into one of two inosamine penta-acetates, viz. lL-2-amino-2-deoxy-l-0-methyl-a//o-inositol and 1d-3-amino-3-deoxy-4-0-methyl-c/ /ra-inositol penta-acetates. The results were discussed in terms of currently held views on displacement reactions with carbohydrate and related sulphonates. 

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