Glucitol , acetyl derivatives

In another reaction sequence, compound 193 was prepared by periodate cleavage of 2-deoxy-2-(2,4-dinitroanilino)-3,4-0-isopropyli-dene-D-glucitol or 2-amino-2-deoxy-3,4-0-isopropylidene-D-glu-citol 1,2-carbamate (see Section II, 5 p. 147). Hydrolysis of the 4-acetamido-4-deoxy-1,2-0-isopropylidene-L-xylopyranose resulting (several steps), or of the N-acetyl derivative formed on treatment of 4-amino-4-deoxy-l,2-0-isopropylidene-L-xylopyranose with acetic anhydride in water, leads to the crystalline pyranose form 193. It is noteworthy that free 4-amino-4-deoxy-L-xylose, which, in alkaline solution, consists of the equilibrium mixture 101a 103a (see... 

In our laboratory we routinely use columns (3 m x 2.2 mm) containing 3% w/w OV-225 at 200°C to obtain baseline resolution of the acetylated derivatives of rhamnitol, arabinitol, xylitol, mannitol, galacti-tol, and glucitol in approximately 45 min (Selvendran et al., 1979). With high quality columns containing OV-225, it may also be possible to achieve partial resolution of the acetylated derivatives of rhamnitol and fucitol. 

Mono-, di-, and tri-saccharides can be separated satisfactorily by g.l.c. of their trimethylsilylated oxime derivatives, and an investigation has been conducted into the most selective stationary phases for the separation of mixtures of pentoses and hexoses as their TMS derivatives. Traces of D-glucose and other related impurities in samples of o-glucitol can be detected by g.l.c. of the O-acetyl derivatives. ... 

Intramolecular cyclization can also be effected with acyclic intermediates derived from such readily available alditols as D-mannitol. Kuszmann and Vargha63 reported the formation of 2,5-anhydro-l,6-dibromo-l,6-dideoxy-4-0-(methylsulfonyl)-D-glucitol (63), in 73% yield, by boiling 3,5-di-0-acetyl-l,6-dibromo-l,6-dideoxy-2,4-di-0-... 

Tri-0-acetyl-l,5-anhydro-2-deoxy-D-arabino-hex-l-enitol (tri-O-acetyl-D-glucal) was the starting point for the synthesis of 1,5-anhy-dro-2-chloro-2-deoxy-D-glucitol or -D-mannitol by way of the 1,2-dichloride (22), which was reduced32 by means of lithium aluminum hydride to the 2-chloro-2-deoxy derivative (23). That the chlorine... 

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