(2,3-Di-O-acetyl-6-deoxy-6-iodo)-hexakis(2,3,6-tri-O-acetyl) cyclomaltoheptaose (9) was prepared by reaction of cyclomaltoheptaose (5) with trityl chloride followed by acetylation, O-detritylation, mesylation, and displacement of the mesyloxy group by iodine using sodium iodide. This cyclomaltoheptaose derivative was S-glycosylated in high yield with either of the anomers of 2,3,4,6-tetra-O-acetyl-S-acetyl-1-thioglucopyranose (1α or 1β). Deacetylation afforded S-(α -D- and S-(α-D-glucopyranosyl)-6-thiocyclomaltoheptaose (10b) and 11b, respectively. Procedures arising from model experiments also provided a new syntheses of S-(α-D-glucopyranosyl)-6-thiomaltose (3b) and of its β-isomer (4b).