The present paper is concerned with further researches on reduction products of diaryl, tetraazo-trithioderivatives Ar₂N₄C₂S₃H₂, which have already been described and obtained by oxidation of aryl, dithiocarbazic acids. By reaction with LiAlH₄ and NaBH₄ the following products were formed: arylhydrazine, 1,5-thiocarbohydrazides and derivatives to which the general formula ArN₂C₂S₂H can be ascribed. These latter have not as yet been obtained by other reducing agents. They are the same products which were obtained by Busch as early as 1895, and classified as 4-aryl-2,5 endothio $\Delta^{2}-1$, 3, 4-thiodiazolynes.