Abstract: The reaction product of: (i) a polyalkenyl derivative of an ethylenically unsaturated carboxylic reagent and (ii) a compound of the formula wherein R is a linear alkylene group having at least 2 carbon atoms, a branched alkylene group having at least 3 carbon atoms, a cycloalkylene group having at least 5 carbon atoms, in which one or more of said carbon atoms may be substituted by one or more hetero atoms, or is an aromatic group or a group of the formula in which a is 1 to 6 and b is 0 to 6, wherein the groups R may be the same or different, and wherein the values of a and b may be the same or different; process for the preparation of said reaction product; lubricating oil compositions, fuel compositions and additive concentrates containing such reaction products; and use of the reaction products as dispersant additives.