A compound represented by the formula (I) or a salt thereof; and an agent for protecting a brain/neuronal cell or a therapeutic agent for sleep disorder comprising the compound or salt: wherein Z represents an oxygen or sulfur; R
1
represents an aryl or heterocyclic group which may be substituted, provided that R
1
is not a 3-ethyl-6-methoxy-2-methyl-5-naphthalen-1-yl group; R
1a
represents a hydrogen atom, a hydrocarbon group which may be substituted, a hydroxyl group or the like; R
2
represents a piperidin-1,4-diyl or piperazin-1,4-diyl which may be substituted; R
3
represents a bivalent group which is formed by removing two hydrogen atoms from a benzene ring or 6-membered aromatic heterocyclic ring which may have a substituent, provided that R
3
is not a pyridazin-3,6-diyl; and R
4
represents a group which is formed by removing one hydrogen atom from a benzene ring or 5- to 6-membered heterocyclic ring which may be substituted, provided that the substituent on the heterocyclic ring is not a phenylethyl group which may be substituted when Z is sulfur.
化合物(I)的
化学式或其盐;以及包含该化合物或盐的保护脑部/神经细胞的药剂或治疗失眠症的药剂:其中Z代表氧或
硫;R1代表取代的芳基或杂环基,但R1不是3-乙基-6-甲氧基-2-甲基-5-
萘基-1-基基;R1a代表氢原子,可取代的烃基,羟基或类似物;R2代表可取代的
哌啶-1,4-二基或
哌嗪-1,4-二基;R3代表双价基团,由苯环或6元芳杂环环上去掉两个氢原子形成,可以有取代基,但R3不是
吡嗪-3,6-二基;R4代表由苯环或5-到6-元杂环环上去掉一个氢原子形成的基团,可以取代,但当Z是
硫时,杂环环上的取代基不是可取代的苯乙基基团。