WALTHAM, Mass. (AP) — Oscient Pharmaceuticals Corp. said Monday it has filed for Chapter 11 bankruptcy protection, and sold its chronic bronchitis drug Factive. Oscient and subsidiary Guardian II Acquisition Corp. filed in the U.S. Bankruptcy Court for the District of Massachusetts. The company is seeking relief from its debts while it reorganizes. Oscient agreed to sell one of its two drugs, Factive, to Cornerstone Therapeutics Inc. for $5 million, plus royalties and the value of the drug’s inventory. The company said it will consider strategic alternatives, including seeking a buyer for its only other approved drug, the cholesterol drug Antara, and other assets. Oscient said it expects its shares to be delisted from the Nasdaq on July 21. The company received a notice from the stock exchange on July 10 that it had failed to pay fees required to maintain its listing. Oscient does not plan to appeal the decision. The company’s shares closed at 18.1 cents on Monday. Oscient has cut 280 of its 305 jobs this year as part of an effort to preserve cash and reduce debt. In February, it eliminated 100 jobs, and in June, it cut its 150-person sales force and 30 other positions.