| 摘要 |
The compounds have the formula <IMAGE> in which R<1> is absent or is hydrogen, alkyl or acyl, A is an acyl radical or an amino acid residue, B is an amino acid residue, R<2>, R<3> and R<4> are as defined in the description, and R<9> is -OH or -F, and they and their salts are used as pharmaceuticals. |
