Geminal bisphosphonates and the corresponding acids which are characterized by a P–C–P linkage are stable pyrophosphates analogs which are completely resistant to enzymatic hydrolysis. They are widely used in the treatment of a number of diseases characterized by an abnormal calcium metabolism, such as Paget's disease, osteoporosis.11. Rodan , GA and Martin , TJ 2000. Therapeutic approaches to bone diseases. Science, 289: 1508–1514. ...