| abstract |
A novel amino acid derivative represented by general formula (I) and a salt thereof have been synthesized and it has been found that they promote the growth and physiological action of the T cells of mammals and have an immunomodulator effect and either an antitumor or a carcinostatic effect, and that they also have the effect of promoting the growth of hematopoietic stem cells wherein Y represents 0 or 1; R<1> represents unsusbstituted C1-C8 alkyl, etc.; R<2> represents hydrogen, C1-C5 alkyl, etc.; R<3> represents hydrogen, C1-C8 alkyl, etc.; R<4> represents hydrogen, C1-C3 alkyl, etc.; and R<5> represents -OR<42>, -NR<43>R<44>, etc. |