PROBLEM TO BE SOLVED: To provide a novel thiourea compound useful as a glutaminyl cyclase inhibitor.SOLUTION: This invention relates to a thiourea compound represented by formula (I), where A is the following formula; B is H or methyl; R, R, and Rare alkyl or the like; and Z is a divalent bond group.【課題】グルタミニルシクラーゼの阻害剤として有用な新規チオ尿素化合物の提供。【解決手段】式(I)で表わされるチオ尿素化合物。〔Aは下記式;BはH又はメチル;R1、R5、R6はアルキル等;Zは2価の結合基〕【選択図】なし