Abbreviations: Pyrazon, 5-amino-4-chloro-2-phenyl-3 (2H) pyridazinone; o-methyl-pyrazon, 5-amino-4-chloro-2(2-methylphenyl)-3(2H)-pyridazinone; m-methyl-pyrazon, 5-aminoj4-chloro-2(3-methylphenyl) 43 (2H) -pyridazinone; p-methyl-pyrazon, 5-amino-4-chloro-2(4-methylphenyl) -3 (2H) pyridazinone. Requests for reprints should be sent to Prof. Dr. F. Lingens, Institut für Mikrobiologie und Molekular...
