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The present research describes the preparation of novel mon-azothiazoles and bis-azothiazoles based on hydrazonoyl halides. These thiazoles are prepared from the reaction of 2-(4-(dimethylamino)benzylidene)hydrazine-1-carbothioamide with α-haloketohydrazonoyl halides in the basic medium (triethylamine) at reflux. The process of preparation is designed and illustrated in the manuscript. The mechanism of the final novel mono- and bis-azothiazoles can be described through thiol group of 2-(4-(dimethylamino)benzylidene)-hydrazine-1-carbothioamide undergo nucleophilic attack to carbon attached to halogen from hydrazonoyl to form S-alkylated intermediate. The intermediate is eliminated hydrogen chloride then at once undergoes intramolecular cycloaddition followed by exclusion of water to provide the novel series of mono- and bis-azothiazole. Structures of the final products were elucidated by FTIR, MS, NMR and elemental analyses. These reactions are provided the desired products in excellent yields. The antiproliferation activity of the newly synthesized compounds was evaluated using the MTT assay against human colorectal adenocarcinoma (DLD-1) and human adenocarcinoma (A549) cells. Furthermore, apoptosis induction was also investigated via the estimation of the caspase-3 levels using western blotting and dual staining technique. [ABSTRACT FROM AUTHOR]

Thiadiazine and thiazoles have attracted importance due to their broad applicability as biologically active compounds. New thiadiazines and thiazoles are prepared via the simple reaction of an α-haloketohydrazonoyl with thiocarbohydrazone derivatives in a basic medium under reflux. A S-alkylated intermediate forms through nucleophile substitution involving the hydrazonoyl halogen and thiocarbohydrazone thiol. In situ cyclization via the condensation between the carbonyl and NH2 or NH moieties of the intermediate forms 1,3,4-thiadiazine and thiazole derivatives, respectively. This method employs inexpensive, commercially available reagents and facile reaction conditions to afford novel thiadiazine/thiazole derivatives in good yields. [ABSTRACT FROM AUTHOR]

The present effort is to use good organized method for the synthesis of novel thiazoles from the reaction of different α-haloketohydrazonoyl halides with thiosemicarbazones in the basic medium at refux. In addition, new polthiazole was prepared from the reaction of 1,4-phenylene-bis(2-oxopropanehydrazonoyl chloride) with 2,2′-(1,4-phenylenebis(methanyl-ylidene))bis(hydrazine-1-carbothioamide) in the presence of basic medium. The formation of the final thiazoles or polythiazole can be explained through nucleophile substitution of the halogen atom form hydrazonoyl halides, followed by removal of water to give the final products as represented in Schemes. The inexpensive, good yielding, simple reaction conditions, and commercial availability of the chemicals make these methods valuable. The description structures for the final compounds are discussed and suggested. New organic substances were elucidated via FTIR, MS, NMR, and elemental analyses. [ABSTRACT FROM AUTHOR]

Synthesis and characterization of new thiadiazoles, bisthiadiazoles from the reaction of mono- and di-hydrazonoyl halides with various hydrazinecarbodithioate derivatives were studied. Treatment of hydrazonoyl halides with 2,5-dihydrazinyl-1,3,4-thiadiazole afforded new bistriazines containing thiadiazole; we also examined the reaction of 2,5-dihydrazinyl-1,3,4-thiadiazole with active methylene compounds to afford new pyrazoles containing thiadiazole compounds. The new synthesized compounds were identified by elemental analysis and various spectral data (Fourier transform infrared spectroscopy, mass spectrometry, ¹H and 13C nuclear magnetic resonance). [ABSTRACT FROM AUTHOR]

The present work describes the preparation of new thiadiazoles through a simple intramolecular reaction of mono- and bis-hydrazonoyl halides with methyl hydrogen phenyl carbonimidodithioate or methyl-2-arylidene hydrazinecarbodithioate. The synthetic method involves nucleophilic substitution followed by intramolecular cyclization reactions mediated by evolution of methanethiol. The structures of the title compounds were elucidated by elemental analyses, and FTIR, MS and NMR spectra. [ABSTRACT FROM AUTHOR]