Place raisins in a small dish. Add wine and set aside.
Place chicken between 2 sheets plastic wrap and pound to 1/4-inch thickness. Sprinkle chicken with 1 teaspoon of the salt and 1/2 teaspoon of the pepper; dredge in flour.
Heat oil in a large frying pan over medium-high heat. When oil is hot, add chicken and cook until browned on both sides, about 10 minutes total. Remove chicken and add onion and garlic to pan. Saute for about 2 minutes; then add oregano, remaining salt and pepper, sugar and vinegar. Stir in tomatoes, capers and olives. Add raisins to sauce and stir in chicken ; cook until thickened, about 5 minutes. Return chicken to pan and heat through.
Arrange chicken and sauce on serving platter and sprinkle with chopped parsley. Garnish with tomato roses.