The equilibrium concentrations of E- and Z-isomers of thiazolidin-4-ones containing exocyclic double bonds in positions 2 and 5 of the cycle were determined in DMSO-d(6). The influence of the nature of the substituents on the equilibrium position was found. Electron-releasing substituents stabilize the E, Z-configuration and electron-withdrawing substituents stabilize the Z,Z-configuration. The association constants of E- and Z-2-ethoxycarbonyl-methylenethiazolidin-4-ones with the sodium cation were determined by H-1 NMR spectroscopy.
Synthesis of novel thiazolidin-4-ones by reaction of malonthioamide derivatives with dimethyl acetylenedicarboxylate
作者:Vera S. Berseneva、Alexey V. Tkachev、Yury Yu. Morzherin、Wim Dehaen、Ingrid Luyten、Suzanne Toppet、Vasiliy A. Bakulev
DOI:10.1039/a803543a
日期:——
Novel 2,5-dimethylenethiazolidin-4-one derivatives have been prepared by reaction of malonthioamide derivatives with dimethylacetylenedicarboxylate. These compounds exist as separate (E,Z)- and (Z,Z)-isomers or as a mixture. The (E,Z)-isomer is formed as the initial product which transforms to the (Z,Z)-isomer under mild conditions. The structures of the obtained compounds have been confirmed by IR
Formylation Products of Thioamides; VII<sup>1</sup>. Synthesis of New<i>N</i>-(3-Aminothioacryloyl)-formamidines and<i>N</i>,<i>N</i>′-Bis[aminomethylidene]thioureas by Bisiminoformylation of Thioacetamides and Thiourea with Formamide Acetals
作者:Alexander Knoll、Jürgen Liebscher
DOI:10.1055/s-1984-30729
日期:——
KNOLL, A.;LIEBSCHER, J., SYNTHESIS, BRD, 1984, N 1, 51-53