| 摘要 |
<p>NEW MATERIAL:A bestatin derivative of formula I (R1 is H or OH; R2 is H or 1-7C acyl; R3 and R4 are 1-7C alkyl, hydroxyalkyl, etc.; n is 0 or 1; is the configuration R, S or a combination thereof). EXAMPLE:(2S, 3R)-3-Amino-2-hydroxy-4-phenylbutanoyl-S-leucyl-S-leucine. USE:An immunological activator and a protecting agent against infection capable of enhancing the cellular immunity in a low dose. The oral dose thereof is preferably 50-200mg per adult once a day. PROCESS:An amino acid derivative of formula II (R5 is protecting group of the amino group) is condensed with an amino acid of formula III by the conventional carbodiimide, active ester method, etc. to give the compound of formula I.</p> |
