Heat oven to 350°F. Spray 24 regular-size muffin cups with cooking spray.
Cut each pineapple slice into 4 pieces; set aside. In large bowl, beat cake mix, oil, eggs and reserved pineapple juice with electric mixer on low speed 30 seconds. Beat on medium speed 2 minutes, scraping bowl occasionally.
In small bowl, stir together melted butter and brown sugar. Spoon 1 1/2 teaspoons butter mixture into each muffin cup. Top each with 2 pineapple pieces. Place cherry half, cut side up, in center of pineapple pieces. Spoon 1/4 cup batter into each cup.
Bake 20 to 25 minutes or until toothpick inserted in center comes out clean. Cool 5 minutes. Run knife around edge of cupcakes to loosen; invert onto cookie sheet. Serve warm.