Synthesis of new structurally diverse thiazolidinone-derived compounds based on reaction of isorhodanine with ortho-substituted aldehydes, α-keto- and β-aroylacrylic acids

Various novel structurally diverse thiazolidinone-derived compounds were synthesized from isorhodanine (4-thioxo-2-thiazolidinone) with ortho-substituted aldehydes, arylidene pyruvic and β-aroylacrylic acids. Michael reaction of isorhodanine with arylidene pyruvic and β-aroylacrylic acids providing 2-oxo-4-(2-oxo-4-thioxothiazolidin-5-yl)-4-phenylbutyric and 4-oxo-2-(2-oxo-2,3-dihydrothiazol-4-ylsulfanyl)-4-phenylbutyric acid is presented. Notably, under the long-term heating, reactions of isorhodanine and APAs underwent as a Michael−cyclization cascade lead to structurally different fused thiopyranoid scaffolds. The structures of newly synthesized compounds were established by spectral data and a single-crystal X-ray diffraction analysis.