The present disclosure relates to a compound of formula (1): where R1 through R8, which can be identical or different from each other, each are selected from of the group comprising hydrogen and the radical —(CH2)k—X, where k is a whole number from 1 to 20 and where X is an organic radical comprising a) at least one neutral, protonizable nitrogen atom and/or b) at least one positively charged nitrogen atom, under the provision that at least 1 radical R1 through R8 is not hydrogen. The invention further relates to the production and use of said compound.