Disclosed is a melanin production inhibitor which has an excellent inhibitory activity on the production of melanin and is highly safe. The melanin production inhibitor is represented by general formula (1) (excluding clotrimazole) and/or a pharmacologically acceptable salt thereof. In the formula, A1, A2 and A3 are independently selected from a hydrogen atom, an aryl group which may have a substituent, and an aromatic heterocyclic group which may have a substituent. At least one of A1, A2 and A3 is selected from the aryl group and the aromatic heterocyclic group, the total number of carbon atoms contained in A1, A2 and A3 is 6 to 50 and, when at least two of A1, A2 and A3 represent the aryl groups or the aromatic heterocyclic groups, the adjacent two aryl or aromatic heterocyclic groups may be bound to each other via an alkyl chain or an alkenyl chain to form a ring; m represents an integer of 0 to 2; X represents a hetero atom, a hydrogen atom, or a carbon atom; R1 and R2 are independently selected from a hydrogen atom and an oxo group. When one of R1 and R2 is an oxo group, the other is not present. R3 is selected from a hydrogen atom, and a C1-8 hydrocarbon group in which one or some of hydrogen atoms or carbon atoms may be substituted by a hetero atom or hetero atoms. The number of R3's present in the compound corresponds to X and, when two or more R3's are present, the R3's are independently present and the adjacent two R3's may be bound to each other to form, together with X, a ring, and the terminal of R3 may be bound to a carbon atom to which A1, A2 and A3 are bound, thereby forming a ring.
本发明涉及一种
黑色素生成
抑制剂,其在抑制
黑色素生成方面具有优异的抑制活性,并且非常安全。该
黑色素生成
抑制剂由通式(1)(不包括
克霉唑)和/或其药理学上可接受的盐所表示。在该式中,A1、A2和A3独立地选自氢原子、可能具有取代基的芳基基团和可能具有取代基的芳香杂环基团。A1、A2和A3中至少有一个选自芳基基团和芳香杂环基团,A1、A2和A3所含的碳原子总数为6到50,当A1、A2和A3中至少有两个表示芳基或芳香杂环基团时,相邻的两个芳基或芳香杂环基团可以通过烷基链或烯基链相互结合形成环;m表示0到2的整数;X表示杂原子、氢原子或碳原子;R1和R2独立地选自氢原子和氧代基团。当R1和R2中的一个是氧代基团时,另一个不存在。R3选自氢原子和C1-8烃基,其中一些氢原子或碳原子可能被杂原子或杂原子取代。化合物中R3的数量对应于X,当存在两个或更多的R3时,R3独立存在,相邻的两个R3可以相互结合形成与X一起的环,R3的末端可以与A1、A2和A3结合的碳原子结合,从而形成一个环。