SYNTHESIS AND BIOLOGICAL-ACTIVITIES OF TAN-1511 ANALOGS

TAN-1511 analogues were synthesized and their effects on the prolifera tion of bone marrow cells were examined. To exert potent activity the following conditions are necessary: the configuration of the 2-amino-6 ,7-dihydroxy-4-thiaheptanoic acid moiety must be (2R,6R), long chain a cyl groups (C-14 to C-18) must be bound to both hydroxyl groups, the a mino group must be free or acylated with the long chain fatty acid (ca . C-14) and the peptide moiety must have glutamic acid as a component. Among the synthesized compounds, trisodium (2R,6R)-2-amino-6,7-bis (h exadecanoyloxy)-4-thiaheptanoyl glycyl glutamyl glutamate, which has i mproved solubility, was effective in experimental leukocytopenia in mi ce.