| 摘要 |
NEW MATERIAL:The compound of formula I (R<1> is H, amino or protected amino; R<2> is H, carboxy or protected carboxy; R<3> is H, carboxy or protected carboxy; R<4> is lower alkyl, lower aminoalkyl, etc.; R<5> is H or lower alkyl; R<6> is H, lower aralkyl, etc.). EXAMPLE:(2S,3R)-2-[[ (2S)-2-Amino-3-carbamoylpropionyl ]amino]-3-[[(1S)-1-car-boxy-2-(4-imidazolyl)ethyl]amino]butyric acid. USE:An agent effective to recover the colony-forming and antibody-forming activity of a host having immunodeficiency and to inhibit the metastasis of tumor. PREPARATION:The compound of formula I can be produced by reacting the compound of formula II or its reactive derivative at the carboxyl group with the compound of formula III or its reactive derivative at the amino group in a solvent under cooling or at room temperature. |
