M. M. A. Abdel Rahman

Acylated osazones and anhydro-derivatives

Abstract The phenylosazone acetates from pentoses, 6-deoxyhexoses and hexoses were boiled with acetic anhydride yielding dianhydrophenylosazone acetates of the type (Ia–c). Similarly, p -chlorophenylosazones from d -glucose, l -sorbose and d -arabinose yielded dianhydro- p -chlorophenylosazone acetates. Acetyl chloride reacted with the phenylosazones from d -glucose and d -galactose yielding the N -acetyl-tetra- O -acetyl derivatives (III) and (IV). The phenylosazones from d -glucose and l -sorbose gave a tetra- and a mono- O -benzoyl derivative, respectively, in crystalline form when an insufficient amount of benzoyl chloride was used during benzoylation.

Reactions of heptulose phenylosazones

Phenylosazones of D-gluco-, D-manno- and D-galacto-heptulose gave crystalline 1-N-acetyl- as well as penta-O-acetyl derivatives. Boiling with acetic anhydride converted them into monoanhydro-osazones of the Diels type and into dianhydro-derivatives. The former were also obtained by treatment with methanolic sulphuric acid. Deacetylation of the penta-O-acetyl derivatives afforded dianhydro-osazones of the Percival type.