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21.
Cardiovascular disorders (CVDs) are the leading risk factor for death worldwide, and research into the processes and treatment regimens has received a lot of attention. Tilianin is a flavonoid glycoside that can be found in a wide range of medicinal plants and is most commonly obtained from Dracocephalum moldavica. Due to its extensive range of biological actions, it has become a well-known molecule in recent years. In particular, numerous studies have shown that tilianin has cardioprotective properties against CVDs. Hence, this review summarises tilianin’s preclinical research in CVDs, as well as its mechanism of action and opportunities in future drug development. The physicochemical and drug-likeness properties, as well as the toxicity profile, were also highlighted. Tilianin can be a natural lead molecule in the therapy of CVDs such as coronary heart disease, angina pectoris, hypertension, and myocardial ischemia, according to scientific evidence. Free radical scavenging, inflammation control, mitochondrial function regulation, and related signalling pathways are all thought to play a role in tilianin’s cardioprotective actions. Finally, we discuss tilianin-derived compounds, as well as the limitations and opportunities of using tilianin as a lead molecule in drug development for CVDs. Overall, the scientific evidence presented in this review supports that tilianin and its derivatives could be used as a lead molecule in CVD drug development initiatives.  相似文献   
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The amidation reaction based on catalytic coupling of alcohols with amines previously reported by us, using the pincer complexes 1 and 2 as catalysts, was applied to the generation of polyamides from nonactivated diols and diamines. A range of polymers was prepared, with Mn up to 26.9 kDa. Unlike the traditional syntheses of polyamides based on carboxylic acid derivatives, which require the use of toxic reagents and generate stoichiometric amounts of waste, this process generates only molecular hydrogen as byproduct. Both aromatic and aliphatic diols and diamines were used. Gel permeation chromatography measurements of the dimethylformamide‐soluble polymers and thermal studies of the polyamides were performed. Matrix assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) spectra are also reported. Thermogravimetric analyses studies indicate that the aromatic polyamides (with the exception of the pyridine‐based polyamide) are more thermally stable than the aliphatic ones. This general, environmentally benign method for the synthesis of polyamides is homogeneously catalyzed under neutral conditions by dearomatized ruthenium‐pincer complexes 1 and 2 and proceeds in 1,4‐dioxane under an inert atmosphere. Conditions for polyamidation in the absence of solvent are also reported, using the pincer complex 2 as catalyst. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   
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Methanation of carbon dioxide (CO2) is attractive within the context of a renewable energy refinery. Herein, we report an indirect methanation method that harnesses amino alcohols as relay molecules in combination with a catalyst comprising ruthenium nanoparticles (NPs) immobilized on a Lewis acidic and robust metal–organic framework (MOF). The Ru NPs are well dispersed on the surface of the MOF crystals and have a narrow size distribution. The catalyst efficiently transforms amino alcohols to oxazolidinones (upon reaction with CO2) and then to methane (upon reaction with hydrogen), simultaneously regenerating the amino alcohol relay molecule. This protocol provides a sustainable, indirect way for CO2 methanation as the process can be repeated multiple times.  相似文献   
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The hydrogen-bond interaction can be studied using a variety of spectroscopic and crystallographic techniques, as well as theoretical studies based on quantum chemical principles, semi-empirical procedures, and statistical interpretations. A degree of specificity, along with flexibility, provides H-bonded systems with a variety of unusual and interesting physical, chemical and biological properties. Neutron diffraction is the method of choice for obtaining high-precision data on hydrogen-atom positions and hydrogen-bond stereo-chemistry in crystals. Neutron inelastic scattering can provide information on the dynamics of H-bonded systems. High-precision neutron diffraction studies on a variety of crystal hydrates, amino acids and small peptides, development of semi-empirical potential functions for bent-hydrogen bonds, and statistical analysis of H-bond populations associated with various donor and acceptor groups are some of the investigations on hydrogen bonding, carried out at Trombay during the past three decades.  相似文献   
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Water is seriously polluted by the discharge of various industrial wastewater containing heavy metals. Among them, chromium is considered to be toxic to living organisms and it is released mostly from tanneries. The chromium-contaminated water is discharged into nearby water bodies and it affects both aquatic and terrestrial plants. So the present experiment was conducted with an aquatic plant, water lettuce (Pistia stratiotes L.) and a terrestrial plant soybean (Glycine max L. Merr.). They were treated with different concentrations (0, 5, 10, 25, 50, 100 and 200mg/L) of potassium dichromate solution. The biochemical parameters such as total chlorophyll, carotenoid, protein and amino acid content and the enzymatic activities like catalase and peroxidase were estimated. The accumulation of chromium was also analysed in both the plants. All the biochemical contents and enzyme activities of water lettuce and soybean seedlings showed a great variation with respect to the increase in chromium concentrations. The accumulation of chromium increased gradually with the increase of chromium concentrations. Total inhibition of all the parameters were observed at 300 mg/L chromium concentration. The terrestrial plant soybean was sensitive than the aquatic plant water lettuce towards chromium stress.  相似文献   
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The synthesis of graphene oxide (GO)–polystyrene (PS) Pickering emulsions, as environment‐friendly nanostructures suitable for novel applications, has received significant attention in recent years. In this work, the synthesis and characterization of GO–PS nanocomposites through seeded emulsion polymerization and the selective light reflection properties of dry films have been reported. Amphiphilic molecule sulfonated 3‐pentadecyl phenol was used as a co‐surfactant to stabilize GO dispersions during the emulsion polymerization process. The particle size of the dispersions as measured by dynamic light scattering decreases from 540 nm, for PS without any GO, to 88 nm with 1 wt% GO content. Scanning electron microscopy studies show a uniform size distribution of the composite particles prepared with GO. The dried films show a structural color that varies with the GO content. The self‐assembly behavior of the dried film was further studied using reflectance spectroscopy, which shows a red shift of the reflectance maximum from 440 to 538 nm as the GO loading was increased from 0.2 to 0.5 wt%, respectively, indicating a different microstructure. X‐ray diffraction, transmission electron microscopy (TEM) and atomic force microscopy (AFM) were used to study the morphology and structure of the composite particles on drying. The AFM study confirms the non‐spherical shape of the particles. Thermogravimetric analysis shows improved thermal decomposition characteristics of the nanocomposite films. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Abstract

Most pressure induced phase transitions are diffusionless. Because of this, there exists a one-to-one correspondence between the positions of atoms in the parent and the product phases, which, therefore, show interesting symmetry relationships. In this paper, we have used these for discussing a symmetry classification of pressure induced phase transitions into four categories: iso-symmetric, group-subgroup, intersection group, and order-disorder transitions. Various examples illustrating this classification scheme are discussed. The importance of this classification is in understanding the mechanism of pressure indbced phase transitions, where both theoretical calculations and experimental measurements are employed to analyse related phenomena like softening of phonon modes, elastic instabilities, diffraction patterns, and orientation relations.  相似文献   
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