Thiazolidinediones are heterocyclic compounds, also known as glitazones, which possess thiazolidine core. This class of compounds is used in the production of drugs for the treatment of diabetes mellitus type 2. Depending on the substituents, the thiazolidinedione derivatives may possess different biological activities such as anti-diabetic, anti-cancer, anti-arthritic, anti-inflammatory, anti-microbial and anti-melanoma. Various studies have been performed showing different biological activities of thiazolidinediones associated with enzymes like aldose reductase (ALR2), histone deacetylase (HDAC), phosphoinositide 3-kinases (PI3Ks), pim kinase, mitogen activated protein kinase (MEK), protein tyrosine phosphatase 1B (PTP1B), tyrosinases, cyclooxygenase-2 (COX-2), UDP-N-acetylmuramoylalanine D-glutamate ligase (MurD ligase). Due to different biological activities, numerous methods for the synthesis of thiazolidinedione derivatives have been developed. Many methods for the synthesis of these compounds are conventional and are not environmentally acceptable due to utilization of various catalysts and organic solvents. In order to reduce the formation of harmful substances during the synthesis, deep eutectic solvents can be used. Deep eutectic solvents are considered green solvents according to their properties like low toxicity, low inflammability, high recyclability and low volatility.

The aim of this work was to synthesize thiazolidinedione derivatives by an environmentally acceptable method. Thiazolidinediones were obtained via Knoevenagel condensation in deep eutectic solvent (choline chloride:N-methylurea) at 80 °C in reactions between substituted benzaldehydes and thiazolidine-2,4-dione. Synthesized thiazolidinediones are obtained in yields from 21.49 % to 90.90 % and compounds showed lipoxygenase inhibition in the range from 7.7 % to 76.3 %.