well, in the 176-191 version, you are just getting 1 extra amino acid added to the fragment as opposed to the the 177
L-Phenylalanine,L-phenylalanyl-L-leucyl-L-arginyl-L-isoleucyl-L-valyl-L-glutaminyl-L-cysteinyl-L-arginyl-L-seryl-L-valyl-L-alpha-glutamylglycyl-L-seryl-L-cysteinylglycyl-, cyclic (7-14)-disulfide