In a large resealable plastic bag, mix orange juice, garlic, oil, chili powder, sugar substitute, orange rind and cayenne pepper. Add chicken breasts; toss to coat. Refrigerate 6 to 8 hours, or overnight.
Heat broiler. Season chicken with salt and pepper. Position broiler rack 6 inches from heat source and broil chicken 12 to 15 minutes, turning halfway through cooking time, just until cooked through.