Green chemistry is a new way of looking at organic synthesis and the design of drug molecules, offering important environmental and economic advantages over traditional synthetic processes. ...Pharmaceutical companies are increasingly turning to the principles of green chemistry in an effort to reduce waste, reduce costs and develop environmentally benign processes.Green Techniques for Organic Synthesis and Medicinal Chemistrypresents an overview of the established and emerging techniques in green organic chemistry, highlighting their applications in medicinal chemistry. The book is divided into four parts:Introduction:Introduces the reader to the toxicology of organic chemicals,their environmental impact, and the concept of green chemistry.Green Catalysis: Covers a variety of green catalytic techniques including organocatalysis, supported catalysis, biocatalysis, fluorous catalysis, and catalytic direct C-H bond activation reactions.Green Synthetic Techniques:Presents a series of new techniques, assessing the green chemistry aspects and limitations (i.e. cost, equipment, expertise). Techniques include reactionsin alternative solvents, atom economic multicomponent reactions, microwave and ultrasonic reactions, solid-supported synthesis, fluorous and ionic liquid-based recycling techniques, and flow reactors.Green Techniques in Pharmaceutical Industry:Covers applications of green chemistry concepts and special techniques for medicinal chemistry, including synthesis, analysis, separation, formulation, , and drug delivery. Process and business case studies are included to illustrate the applications in the pharmaceutical industry.Green Techniques for Organic Synthesis and Medicinal Chemistryis an essential resource on green chemistry technologies for academic researchers, RD professionals and students working in organic chemistry and medicinal chemistry.
The emerging field of green analytical chemistry is concerned with the development of analytical procedures that minimize consumption of hazardous reagents and solvents, and maximize safety for ...operators and the environment. In recent years there have been significant developments in methodological and technological tools to prevent and reduce the deleterious effects of analytical activities; key strategies include recycling, replacement, reduction and detoxification of reagents and solvents.The Handbook of Green Analytical Chemistryprovides a comprehensive overview of the present state and recent developments in green chemical analysis. A series of detailed chapters, written by international specialists in the field, discuss the fundamental principles of green analytical chemistry and present a catalogue of tools for developing environmentally friendly analytical techniques.
Wildfires emit O3 precursors but there are large variations in emissions, plume heights, and photochemical processing. These factors make it challenging to model O3 production from wildfires using ...Eulerian models. Here we describe a statistical approach to characterize the maximum daily 8-h average O3 (MDA8) for 8 cities in the U.S. for typical, nonfire, conditions. The statistical model represents between 35% and 81% of the variance in MDA8 for each city. We then examine the residual from the model under conditions with elevated particulate matter (PM) and satellite observed smoke (“smoke days”). For these days, the residuals are elevated by an average of 3–8 ppb (MDA8) compared to nonsmoke days. We found that while smoke days are only 4.1% of all days (May–Sept) they are 19% of days with an MDA8 greater than 75 ppb. We also show that a published method that does not account for transport patterns gives rise to large overestimates in the amount of O3 from fires, particularly for coastal cities. Finally, we apply this method to a case study from August 2015, and show that the method gives results that are directly applicable to the EPA guidance on excluding data due to an uncontrollable source.
Flavescence dorée phytoplasma (FDp) is a phytopathogenic bacterium associated with Grapevine yellowS disease, which causes heavy damage to viticultural production. Epidemiological data revealed that ...some FDp strains appear to be more widespread and aggressive. However, there is no data on mechanisms underlying the variable pathogenicity among strains. In this research, we employed chromatographic and spectrophotometric techniques to assess how two strains of FDp influence the levels of grapevine phenolic compounds, which are frequently utilized as indicative markers of stress conditions. The results pointed to the upregulation of all branches of phenolic metabolism through the development of infection, correlating with the increase in antioxidative capacity. The more aggressive strain M54 induced stronger downregulation of phenolics’ accumulation at the beginning and higher upregulation by the end of the season than the less aggressive M38 strain. These findings reveal potential targets of FDp effectors and provide the first functional demonstration of variable pathogenicity between FDp strains, suggesting the need for future comparative genomic analyses of FDp strains as an important factor in exploring the management possibilities of FDp.
The various grass-induced epichloëcyclins of the Epichloë spp. are ribosomally synthesized and post-translationally modified peptides (RiPPs), produced as small, secreted cyclopeptides from a ...single gene, gigA. Here, four clustered and coregulated genes (gigA, gigB, gigC, and kexB) with predicted roles in epichloëcyclin production in Epichloë festucae were evaluated through gene disruption. Subsequent chemical analysis indicates that GigB is a DUF3328 domain-containing protein associated with cyclization of epichloëcyclins; GigC is a methyltransferase enzyme responsible for N-methylation of desmethylepichloëcyclins; and KexB is a subtilisin-like enzyme, partly responsible for the propeptide cleavage of epichloëcyclin intermediates. Symbiotic effects on the host phenotype were not observed for gigA, gigC, or kexB mutants, although ΔgigB infection correlated with increased host tiller height and biomass, while only ΔkexB exhibited an effect on endophyte morphology. Disrupting epichloëcyclin biosynthesis showed negligible influence on the biosynthesis of E. festucae-associated alkaloids. Epichloëcyclins may perform other secondary metabolism functions in Epichloë and other fungi.
The imbalance between osteogenesis and osteoclastogenesis is a feature of bone metabolic disease. Cadmium (Cd) exposure causes human bone loss and osteoporosis (OP) through bioaccumulation of the ...food chain. However, the impact of Cd on bone tissues and the underlying molecular mechanisms are not well-characterized. In the current study, we found that the Cd concentration in bone tissues of OP patients was higher than normal subjects; meanwhile, the nuclear silent information regulator of transcription 1 (SIRT1) protein expression level was significantly decreased, which is a new star molecule to treat OP. It is further revealed that SIRT1 activation markedly reprograms bone metabolic and stress-response pathways that incline with osteoblast (OB) apoptosis. Suppressing reactive oxygen species (ROS) release with N-acetyl-l-cysteine (NAC) abolished Cd-induced reduction of SIRT1 protein, deacetylation of P53, OB apoptosis, and attenuated OP. Conversely, overexpression of SIRT1 suppressed Cd-induced ROS release. SIRT1 overexpression in vivo and in vitro dampened PGC-1α protein, acetylation of P53 at lysine 382, and caspase-dependent apoptosis. These results reveal that ROS/SIRT1 controls P53 acetylation and coordinates OB apoptosis involved in the onset of OP.