By Marthe Fourcade - Amgen Inc. (AMGN), the world’s largest biotechnology company, agreed to buy closely held Mustafa Nevzat Pharmaceuticals for almost $700 million to expand in Turkey, where economic growth is boosting demand for medicines. Amgen will pay cash to get 95.6 percent of Mustafa Nevzat, or MN Pharmaceuticals as the Istanbul-based generic-drug maker is known, the companies said in a joint statement. The transaction will boost Amgen’s presence in a region that has “large, fast-growing, priority markets,” they said.