A heterocyclic compound represented by the general formula (1) or a salt thereof:wherein m, l, and n respectively represent an integer of 1 or 2； X represents -O- or -CH2-； R1 represents hydrogen, a lower alkyl group, a hydroxy-lower alkyl group, a protecting group, or a tri-lower alkylsilyloxy-lower alkyl group； R2 and R3, which are the same or different, each independently represent hydrogen or a lower alkyl group； or R2 and R3 are bonded to form a cyclo-C3-C8 alkyl group； and R4 represents an aromatic group or a heterocyclic group, wherein the aromatic or heterocyclic group may have one or more arbitrary substituent(s).本發明關於以通式(1)代表的雜環化合物或其鹽：其中m、l和n各自代表1或2之整數；X代表-O-或-CH2-；R1代表氫、低碳烷基、羥基-低碳烷基、保護基或三-低碳烷基矽氧基-低碳烷基；相同或不同的R2和R3各自獨立代表氫或低碳烷基；或R2與R3鍵結形成環-C3-C8烷基；及R4代表芳族基團或雜環基團，其中芳族或雜環基團可具有一或多個任意的取代基。
