[On analgetically, antipyretically and antiphlogistically active sulphur-containing pyridazines (author's transl)]

12 newly synthetized sulphur-containing pyridazines were tested for analgetic, antipyretic and antiphlogistic activity. Using the tail-flick and the hot-plate test as well as the writhing syndrome as screening procedures, the author stated that 9 of these compounds produced a good analgetic effect. The majority of these compounds exerted a marked antipyretic effect as evidenced by the antipyresis model. The action of these pyridazines on the acute oedema of the rat hind paw was relatively poor. Determination of the acute lethal doses and of adverse effects due to an action on the central nervous system showed that 3 of the 12 compounds under investigation are characterized by low toxicity. Furthermore, the analgetic and antiphlogistic screening methods revealed that one of these 3 compounds, 3-amino-4-mercapto-6-methylpyridazine (1), is particularly active. The beneficial properties of this substance and also those of some other derivatives justify more detailed studies concerning the pharmacological characterization of sulphur-containing pyridazines.