1H-1,4-Benzodiazepine-3-carboxylic acid, 7-chloro-2,3-dihydro-2-oxo-5-phenyl-, monopotassium salt, mixture with 1-(10-(2-(dimethylamino)propyl)-10H-phenothiazin-2-yl)ethanone, 1-(10-(3-(dimethylamino)propyl)-10H-phenothiazin-2-yl)ethanone and potassium hydroxide