For the syrup: Bring the sugar, 1 cup water and lemon zest to a boil. Reduce to a simmer and cook for 5 minutes. Strain and cool. Stir in the lemon juice.
For the chipotle salt: Mix together the chipotle powder and salt and store in an airtight container. Stir together the cherry puree, tequila, 6 ounces of the lemon juice, the chipotle puree and 3 ounces simple syrup. Dip the edge of each glass in the remaining lemon juice, and then in the chipotle salt. Fill the glasses with ice, and then pour over the cherry-chipotle cooler.
For a less spicy drink, scale back on the chipotle puree. If you can't find premade cherry puree, blend fresh or thawed frozen cherries in a blender with just enough water to thin.