Single-crystal and powder X-ray diffraction, 13C CP/MAS NMR, and DFT-GIAO calculations of methyl 3,4,6-tri-O-acetyl-2-O-(2,3,4,6-tetra-O-acetyl-β-d-galactopyranosyl)-α-d-glucopyranoside and methyl 2,4,6-tri-O-acetyl-3-O-(2,3,4,6-tetra-O-acetyl-β-d-gala

► Comprehensive structural analyses were performed for the two unusual disaccharides (1 and 2). ► 1 crystallizes with three molecules in an independent part of the unit cell and consists of one polymorph. ► 2 crystallizes with two molecules in an independent part of the unit cell and consists of two or three polymorphs.