In a small saucepan, heat 1/2 cup water and the sugar over medium heat and stir until dissolved. Let the simple syrup cool.
Fill a pitcher with ice cubes. Add the rum, passion fruit juice, orange juice, pineapple juice, orange liqueur, lime juice and simple syrup and stir until chilled. Strain the cocktail into glasses, top each with a dash of bitters and garnish with a pineapple wedge.