Barbituric acid derivative and preventive and therapeutic agent for bone and cartilage containing the same

The present invention relates to a novel barbituric acid derivative and the method of the prevention and treatment by using the same of malignant hypercalcemia, osteolytic diseases such as Paget's disease of bone and osteoporosis, such diseases with the denaturation and necrosis of a cartilage as osteoarthritis, necrosis of head of femur, and articular rheumatism occurring in a knee, shoulder, and joint. A compound of the formula wherein the substituents are as defined in the specification and solvates and salts thereof useful for treating bone and cartilage diseases.