Two Forms of Anhydrous l-Rhamnose and a New Method for the Preparation of Crystalline β-Tetraacetyl-l-rhamnose¹

Abstract

Vol. 59 isoxazolone-5. Minunni obtained 3-phenylisoxazolone-5 from 3-phenyl-4-benzylidene-isoxazolone-5, but he considered it to be alpha-aminocinnamolactone, a compound which would have the same empirical formula.Reaction with Phenylhydrazine.-The salt was prepared directly from 3-phenylisoxazolone and phenylhydrazine by the method described by Uhlenhuth.* It can be recrystallized in the form of white flakes from methanol; it melts with decomposition to a red liquid at 153-154°. The yield was quantitative. It easily reduced Fehling's solution, showing it to be a phenylhydrazine salt and not a phenylhydrazone. The same salt (plus the corresponding aldehyde phenylhydrazone) was obtained by mixing warm methanol solutions of 3-phenyl-4-benzylideneisoxazolone-5 (1 mole) and phenylhydrazine (2 moles); the same was done with 3-phenyl-4-anisylidene-isoxazo-

Chemistry of the Carbohydrates and Glycosides

“…Configuration of the pyranoid ring.-After many years of con troversy, the ring structures of the methyl glycosides, as originally determined by the methylation method, have been accepted and the configurations of all of the asymetric carbons have been established (3). It is becoming increasingly evident that the configurations of the atoms comprising the sugar ring influence in marked degree the reac tions and properties of the sugars and their derivatives (4,5,6).…”

Alpha and beta methyl lyxosides, mannosides, gulosides, and heptosides of like configuration

“…Several of the glycosides were separated as acetates, which were deacetylated by Isbell's barium methylate method [5]. The new compounds are listed in table 1 The structure of our new .a-methyl d-Iyxoside was determined by the application of the periodic oxidation method of Jackson and Hudson [6]. As shown by Maclay and Hudson [7], a-methyl d-Iyxopyranoside is oxidized by periodic acid according to the following equation: …”

“…Because of the confusion 6 which exists with respect to the nomenclature of the higher sugars, the several systems of nomenclature in current use will be considered, and our compounds will be named in accordance with each system.…”

Cellulose Studies. Part XVI. The Reaction of Cellulose with Formaldehyde

“…Jackson and Hudson [ 11 ] observed the theoretical periodic acid consumptions of 1.0 mole per mole on cellulose and starch.…”