Novel and potent calcium-sensing receptor antagonists: discovery of (5R)-N-[1-ethyl-1-(4-ethylphenyl)propyl]-2,7,7-trimethyl-5-phenyl-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine-3-carboxamide monotosylate (TAK-075) as an orally active bone anabolic agent.