D-myo-Inositol-1,3,4,5,6-pentaphosphate ammonium salt

D-myo-Inositol-1,3,4,5,6-pentaphosphate (ammonium salt) [Ins (1,3,4,5,6) P5 (ammonium salt) ] is an isomer of inositol phosphate that functions as a small, soluble second messenger in cellular signaling. It can bind to the PH domain of Grp1 with a dissociation constant (Kd) of 590 nM. This compound inhibits the phosphorylation and kinase activity of Akt/PKB, leading to apoptosis in ovarian, lung, and breast cancer cells. Additionally, it exhibits anti-angiogenic activity in vitro, blocking capillary formation by HUVECs, and demonstrates antitumor effects in cancer xenograft models in nude mice.