DE application 10222192 describes pentafluorosulfanylbenzoylguanidines as NHE1 inhibitors. The processes described therein for preparing these compounds, however, result in low yield and require reagents and reaction-conditions that necessitate great technical complexity or are unsuitable for preparation on a relatively large scale. It has now been found that said disadvantages can be avoided by a novel efficient synthesis which starts from commercially available 4-nitrophenylsulfur pentafluoride.