Synthesis of 4-(4-oxo-1,3-thiazolidin-2-ylidene)-pyrrolidine-2,3,5-triones

2-(4-Oxo-1,3-thiazolidin-2-ylidene)acetamid as promising scaffold for designing new antifungal compounds

1,3-Thiazolidin-4-one derivatives with a exocyclic C=C double bond in position 2 of the hetero ring have a wide spectrum of biological activity, but their fungicidal activity has not been studied as much as it should be. This paper presents a simple and convenient approach for obtaining potential antifungal agents based on 2-(4-oxo-1,3-thiazolidin-2-ylidene)acetamides. The first examples of evaluating the fungicidal activity of 8 obtained compounds on 8 strains of phytopathogenic fungi are presented. A highly active compound 4e with EC50 of 0.85 and 2.29 µg/mL against A. solani and P. lingam, respectively, was found to be promising for further study.

Discovery of Methyl (5 Z)-[2-(2,4,5-Trioxopyrrolidin-3-ylidene)-4-oxo-1,3-thiazolidin-5-ylidene]acetates as Antifungal Agents against Potato Diseases

Synthesis, isomerism, and fungicidal activity against potato diseases of new (5 Z)-[2-(2,4,5-trioxopyrrolidin-3-ylidene)-4-oxo-1,3-thiazolidin-5-ylidene]acetate derivatives with 1,3-thiazolidine-4-one and pyrrolidine-2,3,5-trione moieties linked by an exocyclic C═C bond were described. Their structures were clearly confirmed by spectroscopic and spectrometric data (Fourier transform infrared spectroscopy, ¹H and ¹³C nuclear magnetic resonance, and mass spectrometry), elemental analysis, and X-ray diffraction crystallography. A bioassay for antifungal activity in vitro against Phytophthora infestans, Fusariun solani, Alternaria solani, Rhizoctonia solani, and Colletotrichum coccodes demonstrated that 2,4,5-trioxopyrrolidin-1,3-thiazolidine derivatives exhibited a relatively broad spectrum of antifungal activity. One of the compounds showed considerable activity against all of the strains; in the case of F. solani, P. infestans, and A. solani, it possesses comparable or better fungicidal efficacy than the positive control Consento. Consequently, this compound is a promising fungicidal candidate for plant protection.

Crystal structures of two (Z)-2-(4-oxo-1,3-thia-zolidin-2-yl-idene)acetamides

The crystal structures of two (oxo­thia­zolidin-2-yl­idene)acetamides, namely (Z)-2-[2-(morpholin-4-yl)-2-oxo­ethyl­idene]thia­zolidin-4-one and (Z)-N-(4-meth­oxy­phen­yl)-2-(4-oxo­thia­zolidin-2-yl­idene)acetamide are described and compared with a related structure.

The crystal structures of two (oxo­thia­zolidin-2-yl­idene)acetamides, namely (Z)-2-[2-(morpholin-4-yl)-2-oxo­ethyl­idene]thia­zolidin-4-one, C₉H₁₂N₂O₃S, (I), and (Z)-N-(4-meth­oxy­phen­yl)-2-(4-oxo­thia­zolidin-2-yl­idene)acetamide, C₁₂H₁₂N₂O₃S, (II), are described and compared with a related structure. The Z conformation was observed for both the compounds. In (I), the morpholin-4-yl ring has a chair conformation and its mean plane is inclined to the thia­zolidine ring mean plane by 37.12 (12)°. In (II), the benzene ring is inclined to the mean plane of the thia­zolidine ring by 20.34 (14)°. In the crystal of (I), mol­ecules are linked by N—H⋯O hydrogen bonds, forming C(6) chains along the b-axis direction. The edge-to-edge arrangement of the mol­ecules results in short C—H⋯O and C—H⋯S inter­actions, which consolidate the chain into a ribbon-like structure. In the crystal of (II), two N—H⋯O hydrogen bonds result in the formation of C(8) chains along the b-axis direction and C(6) chains along the c-axis direction. The combination of these inter­actions leads to the formation of layers parallel to the bc plane, enclosing R₄⁴(28) rings involving four mol­ecules.