Pentitols dianhydro

Until 1945 no anhydrides of xylitol or any other pentitol had been described. In that year a patent was granted to Grandel73 to make anhydrides of pentitols by heating them with a catalyst, followed by vacuum distillation. Xylitol on being heated with methionic acid followed by vacuum distillation gave monoanhydroxylitol and a dianhydro-(73) F. Grandel (to Alien Property Custodian), U. S. Pat. 2,375,915 (1945). 

In the pentitol series, xylitol on being heated with acids or with zinc chloride gives crystalline 1,4-anhydroxylitol and a sirupy dianhydro derivative, presumably with the 1,4 2,5-ring structure (6 ),... 

Anhvdro-Alditols. - The synthesis of a whole range of 1,5- and 1,4-anhydro-alditols and their inhibitory effects against glycosidases have been reported. The preparation of 2,5-anhydro-3-deoxy-D-araWno-hexitol by hydrogenation of 2,5 3,4-dianhydro-D-allitol over Pearlman s catalyst has been described. The selective chlorination of pentitols to afford l,5-dichloro-l,5-dideoxy derivatives as well as mono- and di-chloro-l,4-anhydro derivatives has been reported. ... 

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