Psicose composition

The composition of a solution of 3-O-methyl-D-psicose15 at 27° is 31 7 56 6, whereas that of D-psicose is 22 24 39 15. In this case, the methoxyl group in the / -pyranose form (17) is axial, and 1,3-parallel interaction with one of its equatorial neighbors cannot be avoided. There is a similar interaction in the / -furanose form, too, but not in the a anomers. 

The composition of 6-0-methyl-D-ii/ to-2-hexulose (6-O-methyl-D-tagatose) in aqueous solution at 35° is 21% of a-furanose, 69% of/ -fura-nose, and 10% of the keto form.15 The ratio of a- to / -furanose for 6-0-methyl-D-psicose was found to be — 2.4 1 that of a- to / pyranose for 5-O-methyl-D-psicose, —1.25 1 the proportion of the keto form was not determined.13... 

Nagata, M., D-Psicose-containing hypoglycemic compositions, foods, and feeds and method for suppression of rapid increase of hlood sugar level, Japanese Patent JP 2005213227 A2 20050811, Jpn. Kokai Tokkyo Koho, 2005, English abstract. 

On the other hand, the product from glucose is an exceedingly complex mixture, the composition of which varies with the conditions of treatment. D-Psicose (from treatment with ammonia) (55) and (dl + n)-sorbose (from treatment with a strong base resin) 90) have been identified definitely in the mixture. D-Glucose is readily converted to D-fructose. From the latter has been isolated after treatment with potassium hydroxide (dl + D)-sor-... 

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