Methyl 2,3,6-tri-o-benzoyl-4-deoxy-4-methoxyamino-alpha-D-glucopyranoside

The crystalline-state conformation of the title compound, C29H29NO9, has be en established unequivocally. The R absolute configuration is observed at t he 4-methoxyamino moiety and the pyranose ring adopts essentially a perfect C-4(1) chair. The torsion angle of the exocyclic hydroxymethyl group is sh own to be gauche-gauche with respect to O1 and C4, respectively. The confor mation along the methoxyamino bond is consistent with that observed for cal icheamicin gamma (I)(1).