A series of novel 3-aryl-5H-pyrrolo[1,2-a]imidazole and 5H-imidazo[1,2-a]azepine quaternary salts were synthesized in 58–85% yields via the reaction of 3-aryl-6, 7-dihydro-5H-pyrrolo[1,2-a]imidazoles or 3-aryl-6,7,8,9-tetrahydro-5H-imidazo[1,2-a]azepines and various alkylating reagents. All compounds were characterized by 1H NMR, 13C NMR, and LC-MS. The conducted screening studies of the in vitro antimicrobial activity of the new quaternary salts derivatives established that 15 of the 18 newly synthesized compounds show antibacterial and antifungal activity. Synthesized 3-(3,4-dichlorohenyl)-1-[(4-phenoxyphenylcarbamoyl)-methyl]-6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-1-ium chloride 6c possessed a broad activity spectrum towards Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, and Cryptococcus neoformans, with a high hemolytic activity against human red blood cells and cytotoxicity against HEK-293. However, compound 6c is characterized by a low in vivo toxicity in mice (LD50 > 2000 mg/kg).
13 March 2017 in Journal of Heterocyclic Chemistry
The article presents the synthesis of 2-arylimino-4-methyl-2,3-dihydro-1,3-thiazoles via Hantzsch reaction of thioureas and 3-chloropentane-2,4-dione or ethyl 2-chloro-3-oxobutanoate. The structure of synthesized compounds was confirmed by LCMS, 1H, and 13C NMR spectra. Cardioprotective activity of synthesized thiazole derivatives were studied in vitro on the isolated rings of the thoracic aorta of laboratory rats. Based on pharmacological studies, the tested compounds possessed a moderate to high cardioprotective effect. A prospective 1-[2-(4-methoxyphenylimino)-4-methyl-3-(4-methylpiperazine-1-yl)-2,3-dihydro-1,3-thiazole-5-yl] ethan-1-one hydrochloride 4c was identified. The mentioned compound has delayed the development of constrictor responses of isolated rings of the thoracic rat aorta and exceeds the activity of L-carnitine by 18.2% and meldonium by 12.9%. The compound 4c may be proposed as a potential cardioprotective agent for in-depth pharmacological studies.
1 September 2014 in Chemistry & Chemical Technology
Our main target and concept was to develop a method for the determination of the most prescribed antilipemic drug, atorvastatin, together with its related substances, with a single sample preparation and during a single chromatographic run, in the shortest possible period of time, with the lowest possible mobile phase consumption. A new rapid, simple chromatographic method for the determination of atorvastatin and its main specified impurities was developed, using different chromatographic columns. With this new concept of a mobile phase and a powerful core–shell, or a superficially porous silica-based column, satisfactory results for targeted parameters, such as critical peak resolution, run time length, and column backpressure, were achieved. The analysis is performed within a run duration of less than 15 min, which is about six times shorter than the official European Pharmacopoeia method. The chromatogram performances suggests that the method limit of quantification (LOQ) can be about 7 times lower, and the limit of detection (LOD) about 20 times lower, using an injection volume of only 2 µl. This was confirmed by the performed method validation in accordance with the International Conference on Harmonization (ICH) guideline for the validation of analytical procedures Q2(R1), where the selectivity, linearity, accuracy, precision, limit of quantification, and limit of detection were tested and confirmed.