Provided is a compound which exhibits bone formation acceleration activity (and/or bone resorption suppression activity). The compound is either a compound having a general formula (I) (wherein the substituents are as defined in the description) or a pharmacologically acceptable salt thereof. The compound or salt has low toxicity, exhibits satisfactory internal behavior, functions to accelerate bone formation, and is useful for the prevention or treatment of metabolic bone diseases associated with bone formation ability which has declined as compared with the bone resorption ability (e.g., osteoporosis, fibrous ostitis (hyperparathyroidism), osteochondrosis, and Paget's disease, which affects systemic bone metabolism parameters).
