PROBLEM TO BE SOLVED: To provide a medicine that inhibits binding of BAFF to a BR3 receptor and excellently prevents and/or treats autoimmune diseases and acquired immunodeficiency syndrome.SOLUTION: The compound is represented by general formula (1) (wherein R1, R2, R3 and R4 are each a 1-4C alkyl group).COPYRIGHT: (C)2013,JPO&INPIT【課題】BR3受容体に対するBAFFの結合を阻害し、自己免疫性疾患、後天性免疫不全症候群の予防及び/又は治療に優れた薬剤の提供。【解決手段】次の一般式(1):(式中、R1、R2、R3、R4は、C1-4アルキル基を示す。)で表される化合物。【選択図】なし