| abstract |
The invention concerns peptides, having the pharmaceutical property of enhancing the immune response, having the structure: <IMAGE> wherein R1 is alkanoyl, Rb1 is hydrogen, methyl, isopropyl, hydroxymethyl, protected hydroxymethyl or benzyl, R2 is hydrogen, carboxy, protected carboxy or a group of the formula: <IMAGE> wherein Ra2 is mono- or di-carboxy (or protected carboxy) lower alkyl or ar(carboxy or protected carboxy) lower alkyl whose aryl moiety is substituted by hydroxy or not substituted, Rb2 is hydrogen or lower alkyl, Rp is hydrogen, carboxy or protected carboxy, Rq is carboxy, protected carboxy or a group of the formula <IMAGE> wherein Ra2 and Rb2 are each as defined above, Rr is hydrogen or amino protective group, m is an integer 1 to 3, and n is an integer 1. |