The present invention relates to indole carboxamide compounds of formula (I) or a salt thereof
wherein R2, R3, R4, R6, R7, R8, R51 and R52 have the meanings as indicated herein, and are MT1 and/or MT2 receptor agonists useful for treating and/or preventing urological diseases.
[Problem]
To provided a compound which is useful as an MT1 and/or MT2 receptor agonist.
[Means for Solution]
The present inventors have conducted studies on MT1 and/or MT2 receptor agonists, and have found that an indole carboxamide compound has an MT1 and/or MT2 receptor agonistic action, thereby completing the present invention. The indole carboxamide compound of the present invention has the MT1 and/or MT2 receptor agonistic action as well as a low CNS penetration, and therefore, it can be used as an agent for preventing and/or treating urological diseases; in one embodiment, lower urinary tract symptoms; in another embodiment, urine storage symptom, in another embodiment, urinary incontinence; in a still another embodiment, stress urinary incontinence; and the like.