抄録
Amino acid derivatives of Racemomycin-A, one of streptothricin group antibiotics, were prepared. Eleven kinds of amino acid were introduced into the amino group in ε-position of the β-lysine moiety of Racemomycin-A by the active esteriftcation method. All the derivatives prepared had an antibacterial activity but less than that of the original antibiotic. Acute toxicity of the derivatives with neutral and acidic amino acid was less than that of the original antibiotic and that of the basic amino derivatives was much lower than that of Racemomycin-C. In all the derivatives, however, prolonged toxicity remained.
