The invention relates to a pharmaceutical product comprising a dibenzofuranone derivative as the active ingredient. The invention further relates to the use of dibenzofuranone derivatives to inhibit kinases, in particular serine/threonine kinases, to the use of dibenzofuranone derivatives for producing drugs and/or medicinal products for treatment, and to the use of dibenzofuranone derivatives as a diagnostic product for analyzing the role of protein kinases, in particular serine/threonine kinases, in particular protein kinase CK2 in cellular processes, the pathogenesis of diseases, ontogenesis and/or other developmental biological phenomena or relationships.