52498-29-0Relevant academic research and scientific papers
Synthesis of analogs of [8 isoleucine]angiotensin II with variations in position 1
Khosla,Hall,Smeby,Bumpus
, p. 431 - 433 (1974)
[Des Asp1,Ile8], [Pro1,Ile8], [MePhe1,Ile8], [Me2Gly1,Ile8], [MeAla1,Ile8], [MeIle1,Ile8] and [Gac1,Ile8]angiotensin II, synthesized by Merrifield's solid phase procedure, possess 0.4, 0.7, 0.9, 0.6, 1.0, 0.7 and 0.7% pressor activity of angiotensin II (vagotomized, ganglion blocked rats) and pA2 values (rabbit aortic strips) of 8.04, 8.52, 8.34, 8.87, 9.03, 8.73, and 9.21, respectively. The comparative pA2 value obtained for [Sar1,Ile8]angiotension II was 9.17. These results suggest that antagonism to contractile response of angiotensin II was reduced when position 1 in [Sar1,Ile8]angiotensin II was replaced by a hydrogen atom or a cyclic imino acid (proline). Antagonistic activity was also reduced when the α carbon atom of sarcosine was substituted with an aromatic side chain (N methylphenylalanine). In contrast, the presence of a branched aliphatic residue at the α carbon atom (N methylisoleucine), an additional methyl group at the nitrogen atom of sarcosine (dimethylglycine), or replacement of sarcosine by a highly basic moiety (guanidineacetic acid) had little effect on the in vitro antagonistic potency of the parent compound.
