Dihexa (CAS 1401708-83-5), also known as PNB-0408 and formally designated N-hexanoic-Tyr-Ile-(6) aminohexanoic amide, is a synthetic oligopeptide with the molecular formula C27H44N4O5 and a molecular weight of 504.66 g/mol. Structurally, Dihexa consists of a dipeptide core of L-tyrosine and L-isoleucine, with an N-terminal hexanoyl (C6 fatty acid) cap and a C-terminal 6-aminohexanoic amide extension. These terminal modifications increase lipophilicity, metabolic stability, and resistance to both aminopeptidase and carboxypeptidase degradation, and were rationally designed based on the structure of angiotensin IV, the endogenous hexapeptide ligand of the AT4 receptor. Produced via solid-phase peptide synthesis, PNB-0408 is associated with hepatocyte growth factor (HGF)/c-Met receptor signalling.

Dihexa is a metabolically stabilised angiotensin IV analogue with a mechanism of action centred on the HGF/c-Met signalling axis. Published research from the originating laboratory has characterised Dihexa as a binder of HGF reported to potentiate HGF activity at the c-Met receptor. In vitro studies in cultured hippocampal neurons have shown that HGF/c-Met signalling drives dendritic maturation and dendrite elongation through Akt/GSK-3β pathway activation, consistent with a broader role for this pathway in neuronal structural plasticity [1]. In vivo rodent studies have examined Dihexa in scopolamine-induced and age-related cognitive deficit models, with published research documenting that orally administered metabolically stabilised angiotensin IV analogues including Dihexa reverse scopolamine-induced deficits in spatial learning and restored spatial-learning measures in aged rodents, characterising the compound as active following systemic administration in rodent models [2], making Dihexa a key reference compound in neuroscience research examining angiotensin-IV-derived peptide modulation of HGF/c-Met signalling and hippocampal neuroplasticity in preclinical models.

Dihexa is manufactured in a cGMP compliant, ISO9001 certified laboratory to a guaranteed purity of 98% or above. Every batch is independently tested using HPLC and MS-UPLC analysis before dispatch. Vials are vacuum sealed and stored in a temperature controlled, monitored cold storage system. Certificates of Analysis are available on request.

Sold strictly for in vitro research purposes only. Not for human consumption. Intended for use by qualified researchers in laboratory settings only.

Editorial Team

Dr. Martina Rossi, PhD

Scientific Contributor and Reviewer

Reviewed and approved 14 June 2026

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