of 4 imidazopropionyl 4 imidazoacetyl or 4 imidazo u03b1 u03b1 dimethyl acetyl r 2 is selected from the group consisting of c 6 c 10 unbranched acyl or is absent r 3 is selected from the group consisting of gly oh or nh 2 and xaa is lys or arg more preferred compounds of formula vii for use in the present invention are those in which xaa is arg and r 2 is c 6 c 10 unbranched acyl even more preferred compounds of formula iv for use in the present invention are those in which xaa is arg r 2 is c 6 c 10 unbranched acyl and r 3 is gly oh other highly preferred compounds of formula iv for use in the present invention are those in which xaa is arg r 2 is c 6 c 10 unbranched acyl r 3 is gly oh and r 1 is 4 imidazopropionyl an especially preferred compound of formula iv for use in the present invention is that in which xaa is arg r 2 is c 8 unbranched acyl r 3 is gly oh and r 1 is 4 imidazopropionyl other preferred glp 1 derivatives are described in u s pat no 6 268 343 b1 a more preferred glp 1 derivative is arg 34 lys 26 n u03b5 u03b3 glu n u03b1 hexadecanoyl glp 1 7 37 preferably the glp 1 compounds comprise glp 1 analogs wherein the backbone for such analogs or fragments contains an amino acid other than alanine at position 8 position 8 analogs the backbone may also include l histidine d histidine or modified forms of histidine such as desamino histidine 2 amino histidine u03b2 hydroxy histidine homohistidine u03b1.