Quiznos has filed for bankruptcy protection, five days after the Sbarro LLC pizza chain did the same, CNNMoney reported. Executives at the restaurant chain, known for its toasted sandwiches, agreed to a restructuring plan that will reduce its debt by more than $400 million, the company said in a statement today. All but seven of the 2,100 Quiznos restaurants in the United States and 30 other countries are independently owned franchises, and will remain open and operating as usual.