In a large skillet, mix sugar with water and bring to a simmer over low heat, stirring until sugar dissolves.
Add wine, orange zest, cinnamon stick and cloves; continue simmering for 15 minutes.
Add plums and poach for 5 to 7 minutes, turning fruit over with a spoon or tongs after 3 minutes, until plums are just tender but still hold their shape.
Using a slotted spoon, remove plums to a serving dish. Raise heat to medium-high and cook syrup until reduced by a third, 5 to 10 minutes longer. Strain to remove spices and pour syrup over plums.