The pro-angiogenic factor HIF-1α is targeted for destruction in non-hypoxic environments by the hydroxylation of a specific proline residue, P564, by the oxygen-sensing enzyme HIF-α prolyl hydroxylase (HIF-PH). Inhibitors of prolyl 4-hydroxylase are potentially useful in controlling excess collagen deposition in pathological fibrosis. 1,4-DPCA is a competitive inhibitor of prolyl 4-hydroxylase in embryonic chick tendon cells and of collagen hydroxylation in human foreskin fibroblasts with an IC50 value of 3.6 and 2.4 μM, respectively. β-oxocarboxylic acids such as 1,4-DPCA have also been found to inhibit the asparaginyl-hydroxylase, factor inhibiting HIF (FIH), with an IC50 value of 60 μM.
![4-OXO-1,4-DIHYDRO-[1,10]PHENANTHROLINE-3-CARBOXYLIC ACID](https://www.chemicalbook.com/CAS/GIF/331830-20-7.gif)