RING TRANSFORMATION OF THE S-(2-OXO-2,3-DIHYDRO-1-BENZO-FURAN-3-YL)ISOTHIURONIUM BROMIDES TO 5-(2-HYDROXY-PHENYL)-2-IMINO-l,3-THIAZOLIDIN-4-ONES

摘要

Synthesis of thirteen substituted 5-(2-hydroxyethyl)-2-phenylimino-1,3-thiazolidin-4-ones is described starting from easily available and stable 5'-(2-oxo-2,3-dihydro-1-benzofuran-3-yl)isothiuronium bromides. The transformation proceeds under mild conditions, is very simple to perform, and is applicable to a wide range of substituents on isothiuronium moiety. Some 1,3-thiazolidin-4-ones show dynamic NMR behavior in solution because of prototropy tautomerism and -EVZ-stereoisomerism. Thermochromic behavior was observed for all synthesized compound.