Melezitose specific rotation

Most of the values reported for the specific rotation of melezitose lie between [qQd +88.1° and +88.8°, as reckoned for anhydrous melezitose by the observers. Richtmyer and the writer48 found [a]D20 +88.5° in water (c, 2) for melezitose monohydrate, CwHjjOu-HaO. Their experience showed that powdered melezitose dihydrate and anhydrous melezitose are transformed rapidly in the air to the stable monohydrate it thus seems doubtful whether the water content of the samples in the older studies was accurately known, and it now appears likely that the samples were essentially melezitose monohydrate. The value [oQn80 +88.5° for melezitose monohydrate corresponds to [a]o 0 +91.7° for anhydrous melezitose, and to [c ]d20 +85.6° for melezitose dihydrate. 

Most of the values reported for the specific rotation of melezitose lie between Ca n +88.1 and +88.8°, as reckoned for anhydrous melezitose by the observers. Richtmyer and the writer" found +88.5 in... 

The data on the specific optical rotation, X-ray diffraction, and on the octa-acetate of the melezitose product were obtained by Professor C. S. Hudson, Dr. Hewitt G. Fletcher, Jr., and Dr. Nelson K. Richtmyer of the Laboratory of Chemistry and Chemotherapy, National Institutes of Health. 

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