Aminosugars. XXI. Conformation of Cyclic Imido Groups Attached to the Glucopyranose-ring

Abstract
Conformation of cyclic imido groups at different positions on O-acetylated-d-glucopyranose-ring was examined from the anisotropic effect of the carbonyls on vicinal ring-protons. The imide-plane at β-C1, C3 were deduced to be slightly inclined counter-clockwise, from the right angle to the mean plane of the pyranose ring, and that at α-C2 and C4 clockwise. 3-Deoxy-1,2 ; 5,6-di-O-isopropylidene-3-phthalimido-α-d-gluco- and -allofuranose were also examined.