It is useful as the remedy method for various diseases, is useful in improvement of gene introduction efficiency to the hemotopoiesis trunk cell at the time of gene remedy, the hemotopoiesis trunk cell and/or the expansion medicine of the hemotopoiesis fore-quarter cell is offered. Formula (i) (X in formula, Y, Z, Ar, R, R, R, R, R, R and R are defined in context.)The hemotopoiesis trunk cell and/or it expands the hemotopoiesis fore-quarter cell the hemotopoiesis trunk cell which features that so tautomerization isomer of chemical compound and the said chemical compound which are displayed, the professional drug or the salt which that medicine can be allowed or it contains those solvent dishes dressed with sauce as the active ingredient, and/or the expansion medicine of the hemotopoiesis fore-quarter cell and the medicine. (Conversion 1)各種の疾患に対する治療方法として有用であり、遺伝子治療時の造血幹細胞への遺伝子導入効率の向上に有用である、造血幹細胞及び/又は造血前駆細胞の増幅剤を提供する。式(I)(式中のX、Y、Z、Ar1、R1、R2、R3、R4、R5、R6及びR7は、本文中において定義される。)で表される化合物、該化合物の互変異性体、プロドラッグ若しくはその医薬的に許容され得る塩又はそれらの溶媒和物を有効成分として含有し、造血幹細胞及び/又は造血前駆細胞を増幅することを特徴とする造血幹細胞及び/又は造血前駆細胞の増幅剤及び医薬。(化1)
