Amezinium. Synthesis and radioactive labelling.

: The synthesis of the novel pharmacologically active substance 4-amino-6-methoxy-1-phenyl-pyridazinium methyl sulfate (ameziniummetilsulfate, LU 1631, Regulton) and the proof of its structure are described. In addition the present paper deals with the microsynthesis of samples which are labelled at a definite site with 14C or 3H, respectively, and which are needed for the examination of its metabolism and the pharmacokinetics.