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141.
Imidazopyridines constitute one of the most important scaffolds in medicinal chemistry, as their skeleton could be found in a myriad of biologically active molecules. Although numerous strategies were elaborated for imidazopyridine preparation in the 2010s, novel eco-compatible synthetic approaches have emerged, conscious of climate change concerns. In this framework, photochemical methods have been promoted to conceive this heterocyclic motif over the last decade. This review covers the recently published works on synthesizing highly functionalized imidazopyridines by light induction. 相似文献
142.
Alaa Eldin M. A. Morshdy Ahmed S. El-tahlawy Sameer H. Qari Alaa T. Qumsani Daniyah Habiballah Bay Rokayya Sami Eman Hillal Althubaiti Ahmed M. A. Mansour Amani H. Aljahani Abd El-Salam E. Hafez Abdallah Fikry A. Mahmoud Rasha M. El Bayomi Mohamed A. Hussein 《Molecules (Basel, Switzerland)》2022,27(7)
Biofilm control by essential oil (EO) application has recently increased to preclude biofilm production on foods and environmental surfaces. In this work, the anti-biofilm effects of garlic and thyme essential oils using the minimum inhibitory concentration (MIC) method against Salmonella typhimurium recovered from different abattoir samples were investigated along with the virulence genes (InvA, SdiA and Stn genes), and the antimicrobial susceptibility profile of S. typhimurium as well. The obtained results revealed that S. typhimurium contaminated abattoir samples to varying degrees. The InvA gene was investigated in all isolates, whereas the SdiA and Stn genes were observed in four and three isolates, respectively. Utilizing the disc diffusion method, S. typhimurium isolates demonstrated substantial resistance to most of the examined antibiotics with a high multiple antibiotic resistance index. S. typhimurium isolates demonstrated biofilm formation abilities to various degrees at varied temperatures levels (4 °C and 37 °C). In conclusion, the obtained samples from the research area are regarded as a potential S. typhimurium contamination source. Furthermore, garlic essential oil (GEO) has more potential to inhibit S. typhimurium biofilm at different sub-minimum inhibitory concentrations as compared to thyme essential oil (TEO). Therefore, these EOs are considered as potential natural antibacterial options that could be applied in food industry. 相似文献
143.
Abdallah Laradji 《代数通讯》2013,41(9):3104-3113
We give several characterizations of Zimmermann's uniform chain condition on matrix subgroups. In particular, we prove that a family of modules satisfies it precisely when the direct sum of their pure injective envelopes splits in their direct product. We also prove that a weaker non-uniform version of this condition is equivalent to Σ-algebraic compactness of reduced products. 相似文献
144.
145.
Hamdi M. Hassaneen Tayseer A. Abdallah Hyam A. Abdelhadi Huwaida M. E. Hassaneen Richard M. Pagni 《Heteroatom Chemistry》2003,14(6):491-497
2‐Dimethylaminomethylene‐ and 2‐ethoxymethylene‐1,3‐indendione 1a,b react with 6‐amino‐2‐thioxopyrimidin‐4(3H)‐one 2 in boiling acetic acid to give 2‐thioxo‐1,3‐dihydroindeno[3,2‐d]pyrimidino[4,5‐b]pyridine‐4,9‐dione ( 4 ). The latter compound reacts with hydrazonoyl chlorides 5a–c to afford products 12a–c . Formamidine 15 reacts with indene‐1,3‐dione in boiling ethanol to give acyclic compound 16 , which cyclizes to 12a in boiling glacial acetic acid. Also, enaminone 1a reacts with heterocyclic amines 17a–e in boiling ethanol, affording the corresponding substitution products 18a–c , respectively. The latter products 18a–c cyclize in glacial acetic acid to give 19a–c , respectively. The structures of the newly synthesized compounds are established on the basis of chemical and spectroscopic evidence. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:491–497, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10166 相似文献
146.
Tayseer A. Abdallah 《Journal of heterocyclic chemistry》2007,44(4):961-965
147.
A new simple extractive spectrophotometric method has been developed for the determination of levofloxacin (I), norfloxacin (II), and ciprofloxacin (III) in pure form and tablets. The method is based on the formation of blue‐colored ion‐pair associates between the drugs and the inorganic complex, cobalt (II) thiocyanate, at pH 2.5. Those ion‐pair associates are readily extracted into an n‐butanol‐dichloromethane solvent mixture (3.5:6.5) and determined spectrophotometrically at 623 nm. The concentration range is 20–240 μg mL?1 for the three studied drugs. The proposed method was successfully applied to determine these drugs in their tablet formulations, and the results are in good agreement with those obtained by the reference methods. 相似文献
148.
Two series of 7‐arylazo‐7H‐3‐(2‐methyl‐1H‐indol‐3‐yl)pyrazolo[5,1‐c][1,2,4]triazol‐6(5H)‐ones 4 and 7‐arylhydrazono‐7H‐3‐(2‐methyl‐1H‐indol‐3‐yl)‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazines 7 were prepared via reactions of 4‐amino‐3‐mercapto‐5‐(2‐methyl‐1H‐indol‐3‐yl)‐1,2,4‐triazole 1 with ethyl arylhydrazono‐chloroacetate 2 and N‐aryl‐2‐oxoalkanehydrazonoyl halides 5 , respectively. A possible mechanism is proposed to account for the formation of the products. The biological activity of some of these products was also evaluated. 相似文献
149.
Jordan C. T. Reddel Kelly E. Lutz Abdallah B. Diagne Prof. Regan J. Thomson 《Angewandte Chemie (International ed. in English)》2014,53(5):1395-1398
The development of a stereoselective one‐pot oxidative [3,3] sigmatropic rearrangement/Friedel–Crafts arylation that provides enantioenriched benzhydryl compounds is reported. The utility of this new transformation is demonstrated by the concise synthesis of several tetralone‐ and naphthyl‐type lignan natural products, many of which display anti‐malarial activity. 相似文献
150.
Abu Elella Mahmoud H. Abdallah Heba M. Gamal Heba Moustafa Essam B. Goda Emad S. 《Cellulose (London, England)》2022,29(13):7317-7330
Cellulose - Antimicrobial hydrogels have enticed a major concern for repairing soft tissues, particularly prohibiting bacterial infections that are frequently accompanied by impaired wound healing.... 相似文献