Preheat your oven to 350°F and grease 24 wells of a muffin tin with non-stick spray. In a mixing bowl, combine the reserved pineapple juice with the yellow cake mix, oil, and eggs, stirring until the batter is smooth and fully incorporated. Slice each pineapple ring into four equal parts. Stir together the melted butter and brown sugar, then spoon approximately 1 teaspoon of this mixture into the base of each muffin well. Place two pineapple segments into each well, followed by a cherry half, cut side facing upward. Fill each well with cake batter, leaving about a ¼-inch space from the rim. Bake for 20 to 25 minutes until the tops are golden. After baking, let the cupcakes cool in the pan for 15 minutes. Carefully run a knife around each to loosen and invert them onto a wire rack to finish cooling.