Abstract: Antiviral (3-ethoxypropionate) esters of (+)-cyclaradine having the formula: ##STR1## In the monoester Ry and Rz are hydrogen. In the diester Ry is the 3-ethoxypropionyl group and Rz is hydrogen. In the triester, Ry and Rz are each 3-ethoxypropionyl groups.