A compound of the formula: ##STR1## wherein each R.sup.1, R.sup.2 and R.sup.3 is an aliphatic acyl group, X is an amino acid sequence consisting of 1 to 5 amino acid residues which contain at least one acidic amino acid residue, n is an integer of 0 to 4, provided that when n is 0, X has glutamyl-glycyl at its N-terminal and when n is 1 or 2, the acidic amino acid residue is an acidic amino acid residue other than D-glutamyl, or a salt thereof has an activity of remarkably improving anhematopoiesis and is useful as an immuno-stimulating agent having a leukocyte-increasing activity.
化合物的公式为:##STR1## 其中每个R.sup.1,R.sup.2和R.sup.3都是脂肪族酰基,X是由1到5个
氨基酸残基组成的
氨基酸序列,其中至少包含一个酸性
氨基酸残基,n是0到4的整数,但当n为0时,X在其N端具有谷
氨酰-甘
氨酰,当n为1或2时,酸性
氨基酸残基是除D-谷
氨酰以外的酸性
氨基酸残基或其盐具有显著改善造血功能的活性,并且作为具有增加白细胞活性的免疫刺激剂是有用的。