Cyclocondensation of Thioamides and Haloacetic Acid Derivatives Provides Only 4-Thiazolidinones; Isomeric 5-Thiazolidinones Were Not observed

Abstract

Cycloaddition of intermediates formed from the nucleophilic addition of aryl isothiocyanate to acidic cyanomethylenes and α-halocarbonyl compounds gave only 4-thiazolidinones. 5-Thiazolidinones were not observed. Cyano-(4-oxo-3-phenylthiazolidin-2-ylidene)-acetic acid ethyl ester (1) and cyano-[5-(4-methoxybenzylidene)-4-oxo-3-phenylthiazolidin-2-ylidene]-acetic acid ethyl ester (2a) also were shown to exhibit moderate antiviral activity.

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GRAPHICAL ABSTRACT

Keywords:

• Cyclocondensation
• 4-thiazolidinones
• 5-thiazolidinones
• X-ray

ACKNOWLEDGMENT

We are grateful to Chris Tseng, Division of Microbiology and Infectious Diseases, NIAID/NIH, Bethesda, MD, USA, for in vitro evaluation of antiviral activity.