COMPOSITION of water, POLYMERS, CATALYSTS, INORGANIC chemistry, and POWER resources
Abstract
The article discusses research on how the light-induced splitting of water into oxygen and hydrogen generates storable polymers and chemical fuels that could be used to address the world's energy demands. Particular attention is also given to the use of inorganic materials as semiconductor catalysts for such splits.
SUSTAINABILITY, COVID-19 pandemic, SUSTAINABLE chemistry, UNDERGRADUATES, PHYSICAL constants, and CHEMICAL laboratories
Abstract
In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with them, or invite responses, or both. "Classroom" is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science. Amidst the Covid-19 pandemic, we have planned a strategy for our institution which aims towards reuse and reduce principles of Green Chemistry. Organic preparations in the undergraduate curriculum can be utilized for other sister laboratory experiments such as recrystallization, determination of physical constants (m.pt) and detection of extra elements, detection of functional group and in qualitative analysis. The product of preparation can also be subjected to a second synthesis. This approach will reduce the amount of chemicals needed for carrying out experiments other than organic preparations. This paper illustrates a few organic preparations which can be reused for other companion laboratory exercises. This approach may set a model towards sustainability for other undergraduate laboratories. [ABSTRACT FROM AUTHOR]
Chalcones have been well examined in the extant literature and demonstrated antibacterial, antifungal, anti-inflammatory, and anticancer properties. A detailed evaluation of the purported health benefits of chalcone and its derivatives, including molecular mechanisms of pharmacological activities, can be further explored. Therefore, this review aimed to describe the main characteristics of chalcone and its derivatives, including their method synthesis and pharmacotherapeutics applications with molecular mechanisms. The presence of the reactive α,β-unsaturated system in the chalcone's rings showed different potential pharmacological properties, including inhibitory activity on enzymes, anticancer, anti-inflammatory, antibacterial, antifungal, antimalarial, antiprotozoal, and anti-filarial activity. Changing the structure by adding substituent groups to the aromatic ring can increase potency, reduce toxicity, and broaden pharmacological action. This report also summarized the potential health benefits of chalcone derivatives, particularly antimicrobial activity. We found that several chalcone compounds can inhibit diverse targets of antibiotic-resistance development pathways; therefore, they overcome resistance, and bacteria become susceptible to antibacterial compounds. A few chalcone compounds were more active than conventional antibiotics, like vancomycin and tetracycline. On another note, a series of pyran-fused chalcones and trichalcones can block the NF-B signaling complement system implicated in inflammation, and several compounds demonstrated more potent lipoxygenase inhibition than NSAIDs, such as indomethacin. This report integrated discussion from the domains of medicinal chemistry, organic synthesis, and diverse pharmacological applications, particularly for the development of new anti-infective agents that could be a useful reference for pharmaceutical scientists. [ABSTRACT FROM AUTHOR]
Stini, Naya A., Gkizis, Petros L., and Kokotos, Christoforos G.
Green Chemistry; 9/7/2022, Vol. 24 Issue 17, p6435-6449, 15p
Subjects
ORGANIC solvents, PEPTIDES, POISONS, FIELD research, RESEARCH teams, ORGANIC synthesis, and SOLVENTS
Abstract
Dihydrolevoclucosenone (Cyrene is its market name) is a biomass-derived solvent that can be produced in only two steps from biomass, while being biodegradable, non-mutagenic and non-toxic. Its "green" profile combined with its physical properties makes Cyrene a plausible substitute for a number of widely used toxic organic solvents. The first attempt to assess Cyrene as a solvent dates back to 2014 and since then, numerous research groups have opted for this promising alternative. Cyrene has successfully been employed as a solvent in materials chemistry, peptide chemistry, organic synthesis and many more research fields, which are going to be discussed in the context of this review. [ABSTRACT FROM AUTHOR]
Chemistry - A European Journal; 1/26/2021, Vol. 27 Issue 6, p1865-1869, 5p
Subjects
SUSTAINABLE chemistry, ORGANIC synthesis, CHEMICAL engineering, CHEMICAL processes, INORGANIC chemistry, AMMONIUM sulfate, and METHACRYLATES
Abstract
Keywords: green chemistry; industrial chemistry; organic synthesis; synthetic methods EN green chemistry industrial chemistry organic synthesis synthetic methods 1865 1869 5 01/29/21 20210126 NES 210126 B Making industry greener b : Many principles for the economic production of organic bulk chemicals, the syntheses of which have potentially the highest environmental impact, currently overlap with principles of green chemistry. For about 93 % of the 250 million tons organic chemicals produced annually by oxidation, oxygen is used as the oxidant, in most cases in combination with catalysts to achieve appropriate selectivities.[3] I Addressed Principles of Green Chemistry: Prevent Waste, Atom Economy, Reduce Derivatives, Catalysis vs. Getting Greener: Propylene Oxide O SB 2 sb is not always the most efficient oxidant, as shown in the different synthetic routes to valuable propylene oxide (Scheme 4).[5] The chlorohydrin process uses chlorine and produces CaCl SB 2 sb as the by-product and is therefore not that green. This would allow the entry into a circular economy.[18, 19] Certain initiatives involving large chemical producers were recently started to introduce a circular economy based on chemcycling in order to replace the current linear use of feedstocks.[20] Greener alternatives should also be as economic as possible. [Extracted from the article]
Efficient conversion of light from short wavelengths to longer wavelengths using color conversion layers (CCLs) underpins the successful operation of numerous contemporary display and lighting technologies. Inorganic quantum dots, based on CdSe or InP, for example, have received much attention in this context, however, suffer from instability and toxic cadmium or phosphine chemistry. Organic nanoparticles (NPs), though less often studied, are capable of very competitive performance, including outstanding stability and water-processability. Surfactants, which are critical in stabilizing many types of nano-structures, have not yet been used extensively in organic NPs. Here we show the utility of surfactants in the synthesis and processing of organic NPs by thoroughly characterizing the effect of ionic and non-ionic surfactants on the properties of fluorescent organic NPs. Using this information, we identify surfactant processing conditions that result in nearly 100 % conversion of organic fluorophores into sub-micrometer particles, or nano-dots, with outstanding performance as CCLs. Such water dispersions are environmentally benign and efficiently convert light. They can be used for a range of fluorophores covering a full spectral gamut, with excellent color purity, including full-width at half-maximum (FWHM) values as low as 21 nm. Compared to inorganic (InP) reference CCLs, the organic nano-dot based CCLs show superior color conversion efficiency and substantially improved long-term stability. Compared to inorganic nanoparticles, organic nanoparticles aren't as well understood. Here the authors explore the use of surfactants to prepare organic semiconductor nanoparticles with outstanding photophysical properties. [ABSTRACT FROM AUTHOR]