Disulfide cyclized tripeptide analogues of angiotensin IV as potent and selective inhibitors of insulin-regulated aminopeptidase (IRAP)

• The insulin-regulated aminopeptidase (IRAP) localized in areas of the brain associated with memory and learning is emerging as a new promising therapeutic target for the treatment of memory dysfunctions. The angiotensin II metabolite angiotensin IV (Ang IV, Val1-Tyr2-Ile3-His4-Pro5-Phe6) binds with high affinity to IRAP and inhibits this aminopeptidase (Ki = 62.4 nM). Furthermore, Ang IV has been demonstrated to enhance cognition in animal models and seems to play an important role in cognitive processes. It is herein reported that displacement of the C-terminal tripeptide His4-Pro5-Phe6 with a phenylacetic acid functionality combined with a constrained macrocyclic system in the N-terminal affords potent IRAP inhibitors that are less peptidic in character than the hexapeptide Ang IV. The best inhibitors in the series, compound 8 and 12, incorporating a 13- and 14-membered disulfide ring system, respectively, and both with a β3-homotyrosine residue (β3hTyr) replacing Tyr2, exhibit Ki values of 3.3 nM and 5.2 nM, respectively.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Läkemedelskemi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Medicinal Chemistry (hsv//eng)

Keyword

angiotensin IV

insulin-regulated aminopeptidase

inhibitor

disulfide

NAMFIS

Pharmaceutical chemistry

Läkemedelskemi

Medicinal Chemistry

Läkemedelskemi

Publication and Content Type

ref (subject category)

art (subject category)