The conformational maps of eight derivatives of the disaccharide α-D-Galp-(1→3)-β-D-Galpsulfated in different positions were obtained using the MM3 force-field specially parameterized for sulfate ester groups. As occurred with MM2, the conformational flexibility of the glycosidic linkage is only slightly hindered by sulfation. A substantial effect of sulfation of the β-D-galactose unit on position 4 shifts the global minimum to positive ΨH(C1′-O3-C3-H3) angles, while sulfation at position 2 of the same unit deepens the well at negative ΨHangles. On the other hand, sulfation on the α-D-galactose unit has a lesser effect, which in any case tends to stabilize the minimum at negative ΨHangles.