For many decades, the thiazole moiety has been an important heterocycle in the world of chemistry. The thiazole ring consists of sulfur and nitrogen in such a fashion that the pi (π) electrons are free to move from one bond to other bonds rendering aromatic ring properties. On account of its aromaticity, the ring has many reactive positions where donor–acceptor, nucleophilic, oxidation reactions, etc., may take place. Molecules containing a thiazole ring, when entering physiological systems, behave unpredictably and reset the system differently. These molecules may activate/stop the biochemical pathways and enzymes or stimulate/block the receptors in the biological systems. Therefore, medicinal chemists have been focusing their efforts on thiazole-bearing compounds in order to develop novel therapeutic agents for a variety of pathological conditions. This review attempts to inform the readers on three major classes of thiazole-bearing molecules: Thiazoles as treatment drugs, thiazoles in clinical trials, and thiazoles in preclinical and developmental stages. A compilation of preclinical and developmental thiazole-bearing molecules is presented, focusing on their brief synthetic description and preclinical studies relating to structure-based activity analysis. The authors expect that the current review may succeed in drawing the attention of medicinal chemists to finding new leads, which may later be translated into new drugs.

The alkylation of benzene with propane to yield isopropylbenzene proceeds with high selectivity over bifunctional metal-acid catalysts comprising Pt and Keggin heteropoly acid in a fixed-bed reactor at 250-350 o C and 1 bar pressure. Most efficiently the reaction occurs over Pt/H 4 SiW 12 O 40 /SiO 2 catalyst at 300 o C, giving isopropylbenzene with 90-93% selectivity at 6-8% benzene conversion, significantly exceeding the efficiency of previously reported Pt/HZSM-5 catalyst. The alkylation proceeds through bifunctional reaction pathway including dehydrogenation of propane to propene (1) on Pt sites followed by benzene alkylation with propene (2) on acid sites. At Pt loadings above 0.5%, step (1) is at fast quasi-equilibrium, and step (2) is the rate-limiting one.

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A world without plastics is unimaginable now and probably also in future. With the growing use of plastic, the problem of waste plastic disposal is also growing. Recycling the plastics is a promising option to avoid the serious environmental challenge caused by them. Among the various options for recycling, catalytic conversion of plastics to hydrocarbons is very attractive. Catalytic pyrolysis depolymerizes the plastics to an oil which can be used as a liquid fuel. This is a sustainable way to utilize the waste, simultaneously promising to meet the energy demand. We studied the use of sulphated zirconium hydroxide as a catalyst for the pyrolysis of different types of plastics such as polypropylene, low density polyethylene, high density polyethylene and a mixture of all three. The objective was to understand the effect of the catalyst and the temperature on the composition of the oil as well as to find an optimum condition for maximum oil yield. Various reaction conditions and their influence on the product distribution are studied. The catalyst is effective in enhancing the reaction rate, altering the product selectivity and narrowing the product distribution of the reaction. At optimum conditions, we obtained more than 79% yield of oil which contains mainly C 10-C 24 hydrocarbons. The fuel properties are suitable to be used as a fossil fuel substitute.

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