1. Chemistry of 1,2,5-thiadiazoles. III. [1,2,5]thiadiazolo[3,4-c][1,2,5]thiadiazole
2. b A. P. Komin and M. Carmack, J. Heterocyclic Chem., in press.
3. a By a Hofmann rearrangement of 4-amino-1,2,5-thiadiazole-3-carboxamide.
4. b by a Curtius reaction of 1,2,5-thiadiazole-3,4-dicarbohydrazide; and
5. c by a Schmidt reaction of 1,2,5-thiadiazole-3,4-dicarboxylic acid: R. Y. Wen, Ph. D. Dissertation, Indiana University, 1962.