Synthesis of Spiro Thiopyrano[2,3-d]thiazolidines. -A homo coupling reaction after treatment of the 4-oxo-thioxo-1,3-thiazolidines (I) with Lawesson reagent leads to title compounds (II). Structure elucidation including X-ray analysis and a discussion of the reaction mechanism are given. -(ELGAZWY*, A.-S. S. H.; ATALLAH, S. R. M.; YASINZAI, M.; MANDEL, S. M.; BAUER, J. A. K.; Mendeleev Commun.