PURPOSE: To obtain a new compound useful for treating and preventing human or animal viral infections, especially infection with human immunodeficiency virus, cat immunodeficiency virus or the like.

CONSTITUTION: The objective compound is a sulfated glycoside selected from sulfated steryl glycosides and sulfated spiroketyl steroid glycosides, which sulfated glycoside has; a hydrophobic moiety selected from sterol aglycone groups each having a steryl group and spiroketal steroid aglycone groups each having a spiroketyl steroid group, where each the aglycone group has a 3-oxy-glycoside linkage; at least one saccharide unit coupled to the aglycone group via a 3-oxy- glycoside linkage of the aglycone group; and at least one sulfated eater of a hydroxyl group which forms a part of the saccharide unit; e.g. β-sitosteryl β-D-glucosidesterate sulfate, obtained by sulfating a steryl glucoside with chlorosulfonic acid in a solvent, preferably in pyridine.