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11.
Karuppan Venkatapathy Chinnaiyan J. Magesh Gnanamani Lavanya Paramasivam T. Perumal Sekar Prema 《Journal of heterocyclic chemistry》2020,57(4):1936-1955
In the present study, we report the design and eco-benign synthesis of new class of carbazolyl-1,4-dihydropyridine (1,4-CDHP) and carbazolyl-1,8-dioxodecahydroacridine (CAD) derivatives via a three-component coupling reaction of substituted carbazole aldehydes, ethyl acetoacetate/dimedone, and ammonium acetate under solvent-free conditions at 112°C to 115°C. We also report an efficient one-pot synthesis of new class of carbazolyl polyhydroquinoline (CPQ) derivatives via a four-component coupling reaction of substituted ethyl acetoacetate, dimedone, ammonium acetate, and carbazole aldehydes in acetonitrile/water medium (3:1) at 73°C to 75°C in moderate yields. All the products were thoroughly characterized by 1H NMR, 13C NMR, Fourier transform infrared (FTIR), mass spectral, and CHN analysis. The synthesized heterocyclic compounds were evaluated for their in vitro antibacterial activity against pathogenic strains of both Gram-negative and Gram-positive bacteria. Minimum inhibitory concentration (MIC) of the active compounds was evaluated by macrodilution method. The CPQ derivative ( 8a ) displayed superior antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhi with the MIC values of 16.0 to 32.0 μg/mL in comparison with the reference drug. The mechanism of antibacterial action of the CPQ derivatives was investigated via scanning electron microscope (SEM) studies. The molecular docking studies indicate that the CPQ derivative ( 8a ) binds to the cell wall protein of E coli and P aeruginosa by formation of hydrogen bonds with amino acid residues (TYR328 and GLU249) of the bacterial cell wall protein. The 1,4-CDHP, CAD, and CPQ derivatives were either noncytotoxic or exhibited minimal cytotoxicity towards human mononuclear cells from peripheral blood. All the products were evaluated for Lipinski rule of five (RO5) and were found to have good oral bioavailability. 相似文献
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Monisha Prasad Selvaraj Jayaraman Mohamed Ahmed Eladl Mohamed El-Sherbiny Mosaab Abdella Ebrahim Abdelrahman Vishnu Priya Veeraraghavan Srinivasan Vengadassalapathy Vidhya Rekha Umapathy Shazia Fathima Jaffer Hussain Kalaiselvi Krishnamoorthy Durairaj Sekar Chella Perumal Palanisamy Surapaneni Krishna Mohan Ponnulakshmi Rajagopal 《Molecules (Basel, Switzerland)》2022,27(5)
Natural products in the form of functional foods have become increasingly popular due to their protective effects against life-threatening diseases, low risk of adverse effects, affordability, and accessibility. Plant components such as phytosterol, in particular, have drawn a lot of press recently due to a link between their consumption and a modest incidence of global problems, such as Type 2 Diabetes mellitus (T2DM), cancer, and cardiovascular disease. In the management of diet-related metabolic diseases, such as T2DM and cardiovascular disorders, these plant-based functional foods and nutritional supplements have unquestionably led the market in terms of cost-effectiveness, therapeutic efficacy, and safety. Diabetes mellitus is a metabolic disorder categoriszed by high blood sugar and insulin resistance, which influence major metabolic organs, such as the liver, adipose tissue, and skeletal muscle. These chronic hyperglycemia fallouts result in decreased glucose consumption by body cells, increased fat mobilisation from fat storage cells, and protein depletion in human tissues, keeping the tissues in a state of crisis. In addition, functional foods such as phytosterols improve the body’s healing process from these crises by promoting a proper physiological metabolism and cellular activities. They are plant-derived steroid molecules having structure and function similar to cholesterol, which is found in vegetables, grains, nuts, olive oil, wood pulp, legumes, cereals, and leaves, and are abundant in nature, along with phytosterol derivatives. The most copious phytosterols seen in the human diet are sitosterol, stigmasterol, and campesterol, which can be found in free form, as fatty acid/cinnamic acid esters or as glycosides processed by pancreatic enzymes. Accumulating evidence reveals that phytosterols and diets enriched with them can control glucose and lipid metabolism, as well as insulin resistance. Despite this, few studies on the advantages of sterol control in diabetes care have been published. As a basis, the primary objective of this review is to convey extensive updated information on the possibility of managing diabetes and associated complications with sterol-rich foods in molecular aspects. 相似文献
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A series of optically active cyclic trans-β-amido alcohols were obtained by the non-enzymatic kinetic resolution of the corresponding racemic amido alcohols using commercially available (S)-BINAP and NCS by SN2 halogenation of the hydroxy group. The product, cis-β-amido chloride, was also obtained in optically active form with an inversion of stereochemistry. 相似文献
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Copper crystals have been grown by Czochralski technique in a 6-bar argon gas environment. X-ray analysis shows that these
are single crystals and are strain-free. A slight pressure environment that is truly hydrostatic seems to improve the quality
of the crystals. Thermal profile estimation results show that the values of temperature which decrease upto the neck region
are same in magnitude as those measured during the experiments and that necking improves the thermal profile and, consequently,
the crystal quality. No facet formation has been observed in these crystals. 相似文献
19.
C. Sekar S. PaulrajG. Krabbes M. KanagarajS. Arumugam Ravhi S. Kumar 《Journal of magnetism and magnetic materials》2011,323(23):3033-3037
MCu2O3 (M=Ca and Co) system has two-leg spin ladder structure similar to that of the prototype SrCu2O3 system except that the rungs are buckled with an angle of 123° and 105° for CaCu2O3 and CoCu2O3 compounds, respectively. We have synthesized powder samples of (Ca1−xCox)Cu2O3 (x=0.00-1.00) by the solid state reaction method and their structural and magnetic properties have been investigated. All the synthesized compounds crystallize in orthorhombic structure with space group Pmmn. Lattice parameters of (Ca1−xCox)Cu2O3 decrease with the increase in Co content. DC magnetic susceptibility χ(T) results of the end products CaCu2O3 and CoCu2O3 show antiferromagnetic transition (TN) at 27 and 215 K, respectively. Co doping into (Ca1−xCox)Cu2O3 enhances its TN systematically with increasing Co concentration. The χ(T) of CoCu2O3 shows a broad transition with the peak temperature around 215 K and it was found to be field independent up to 90 kOe. The ambiguity concerning the transition was ruled out by recording the temperature dependent X-ray diffraction pattern on CoCu2O3 system, which indicated that there is no structural transition in the investigated temperature range of 115-300 K. Further, specific heat measurement on CoCu2O3 confirms the magnetic phase transition by the appearance of a sharp peak at 215 K. 相似文献
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The occurrence of similar structural repeats in a protein structure has evolved through gene duplication. These repeats act as a structural building block and form more than one compact structural and functional unit called a repeat domain. The protein families comprising similar structural repeats are mainly involved in protein–protein interactions as well as binding to other ligand molecules. The identification of internal sequence repeats in the primary structure is not sufficient for the analysis of structural repeats. Thus, a new method called ProSTRIP has been developed using dynamic programming to find the similar structural repeats in a three-dimensional protein structure. The detection of these repeats is made by calculating the protein backbone Cα angles. An internet computing server is also created by implementing this method and enables graphical visualization of the results. It can be freely accessed at http://cluster.physics.iisc.ernet.in/prostrip/. 相似文献