2-Carbaethoxymethylen-3-aethylthiazolidin-4-on, 3-Ethyl-2-ethoxycarbonylmethylen-thiazolidon-(4), Ethyl (3-ethyl-4-oxothiazolidin-2-ylidene)acetate, 2-Ethoxycarbonylmethylen-3-ethyl-thiazolidin-4-on, ((E)-3-ethyl-4-oxo-thiazolidin-2-ylidene)-acetic acid ethyl ester, (3-ethyl-4-oxo-thiazolidin-2-ylidene)-acetic acid ethyl ester