Israel's Teva Pharmaceutical Industries said it would buy U.S. neurology drug company Auspex Pharmaceuticals Inc for an equity value of $3.5 billion to boost its portfolio of treatments for the central nervous system. Teva, the world's largest maker of generic drugs, will offer $101 per share in cash, representing a premium of 42.4 percent to Auspex's Friday closing price, the companies said on Monday.