Heterocyclic macromolecular compound synthesis

In the recent years, various heteroaromatic compouns are being synthesized and their biological activities are being examined. Especially heterocyclic compounds are being investigated against to cancer cells. The potential of 4-thiazolidinones (2,4-thiazolidinediones, 2-thioxo(imino)-4-thiazolidinones) as raw materials of drugs is under consideration by the pharmaceutical science since the beginning of the XX th century. Centerarian history of synthetic research possibilities of that kind of heterocycles lead to diversity in modelling biologically active compounds using 4-thiazolidinone scaffolds. The diversity of biological and physicological activities of organic sulfur heterocycles may be attributed to the presence of the N-C-S fragment, which is characteristic of thiazoles, thiazolines and thiazolidines. Currently 4-thiazolidinones are considered as a new class of antidiabetic (insulin-sensitising) drugs and potent aldose reductase inhibitors, which possess potential for the treatment of diabetic complications (cataract, nephropathy, neuropathy). Novel 4-thiazolidinones are undergoing different stages of clinical trials as potential thyromimetic, antimicrobial, antiviral, anti-ischaermic, cardiovascular, anti-cancer drugs. Bisthiazolidinone derivatives show different pharmacological activities depending on the substituents and types of the groups localized between the thiazolidinone rings which are connected to these moieties by their ring nitrogens. In this study, sixteen new compounds of 2,3-disubstitued-1,3-thiazolidin-4-one and four new 3,3'-bis[2,3-disubstitued-1,3-thiazolidin-4-one] have been synthesized by the technique of one-pot three-component multicomponent reaction (MCR) of various pyridine aldehydes, aminopyridines and mercaptoalcanoic acids. Addition to these, modification of the 2-, 3-, 4- or 5-positions of 4-thiazolidinone ring is successful to achieve synthetic products with a wide spectrum of pharmacological activity. For this purpose, two new 5-hetarylidene-2,3-disubstitued-1,3-thiazolidin-4-one compounds have been synthesized via Knoevenagel condensation reaction of some 2,3-disubstitued-1,3- thiazolidin-4-one compounds with pyridine-2-aldehyde in the presence of sodium ethoxide. The structures of all synthesized compounds have been characterized by ultraviolet, infrared, nuclear magnetic resonance and mass spectral methods. Keywords: 4-Thiazolidinone, multicomponent reaction, Knoevenagel reaction, bisthiazolidinone.