Synthesis of 2-imino-1-thia-3,6-diazaspiro[4,4]non-8-ene-4,7-diones and 2-thioxo-1,3,6-triazaspiro[4,4]non-8-ene-4,7-diones by reactions of pyrrolo[2,1-c][1,4]oxazine-1,6,7-triones with thiourea

The synthesis of thiohydantoins and pseudothiohydantoins spiro-linked to a pyrrol-2-one fragment of pharmacological significance has been developed and supplemented. These 9-aroyl-8-hydroxy-6-(2-hydroxyalkyl)-2-imino-1-thia-3,6-diazaspiro[4,4]non-8-ene-4,7-diones and 9-aroyl-8-hydroxy-6-(2-hydroxyalkyl)-2-thioxo-1,3,6-triazaspiro[4,4]non-8-ene-4,7-diones were obtained by the reaction of 8-aroyl-3,4-dihydropyrrolo[2,1-c][1,4]oxazine-1,6,7-triones with thioureas. The resulting spiro derivatives of pseudothiohydantoin were found to undergo pseudothiohydantoin – thiohydantoin rearrangement.