The adaptation to low oxygen concentrations evoked by chronic or acute hypoxia is mediated by the hypoxia-inducible factor HIF-1. HIF-a levels are affected by changes in the intracellular oxygen concentration. In normoxia the a-subunit is modified posttranslationally by oxoglutarate dependent dioxygenases (prolyl hydroxylases PHD1-3) and rapidly degraded. In hypoxia, HIF-1a is stabilised, dimerises with HIF-1b leading to the transcription of numerous target genes. HIF-1 is also involved in many pathological processes such as ischemic diseases and tumour growth. It is thus an attractive target for pharmacological manipulation. We synthesised a new cell permeable prolyl hydroxylase inhibitor to upregulate HIF-1 in normoxia. 2,4-pyridine dicarboxylic acid (2,4-PDC), an oxoglurarate analogue known from collagen hydroxylases, was esterified and tested for its properties in cell culture studies. ^tBu-2,4-PDC induced HIF-1a accumulation and target gene expression in the low micro molar range in normoxia. Compared to the widely used oxoglutarate analogue dimethyl oxalylglycine (DMOG), ^tBu-2,4-PDC can be used in a 250fold lower concentration. Thus, we have characterised a novel substance to analyse HIF-1 induction in cell culture studies under normoxic conditions.