Iodinated x-ray contrast media

A compound of formula

• wherein three non-adjacent R groups are iodine and the remaining three R groups are non-ionic, hydrophilic moieties, two of which are M groups which comprise an amide group attached to the carbon ring by the carbonyl group or nitrogen atom, and wherein at least one of these M-groups are attached by the nitrogen atom and wherein the amide R groups carry one or more hydroxy or polyhydroxy alkyl groups, and wherein the third R group is a non-amide attached, hydroxy-substituted non-ionic hydrophilic moiety, said compound being water soluble at 20° C. to a concentration of at least 400 mgI/ml and which in aqueous solution at 20° C. at a concentration of 400 mgI/ml has a viscosity no greater than 30.0 mPas.